[Federal Register Volume 69, Number 179 (Thursday, September 16, 2004)]
[Proposed Rules]
[Pages 55896-55927]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-20791]



[[Page 55895]]

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Part III





Department of Transportation





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National Highway Traffic Safety Administration



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49 CFR Parts 571 and 585



Federal Motor Vehicle Safety Standards; Tire Pressure Monitoring 
Systems; Controls and Displays; Proposed Rule

  Federal Register / Vol. 69, No. 179 / Thursday, September 16, 2004 / 
Proposed Rules  

[[Page 55896]]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Parts 571 and 585

[Docket No. NHTSA 2004-19054]
RIN 2127-AJ23


Federal Motor Vehicle Safety Standards; Tire Pressure Monitoring 
Systems; Controls and Displays

AGENCY: National Highway Traffic Safety Administration (NHTSA), DOT.

ACTION: Notice of proposed rulemaking.

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SUMMARY: This notice of proposed rulemaking (NPRM) proposes to 
establish a new Federal motor vehicle safety standard mandating tire 
pressure monitoring systems capable of detecting when a tire is 
significantly under-inflated. A prior version of the standard, adopted 
by the agency in June 2002 in response to a mandate in the 
Transportation Recall Enhancement, Accountability and Documentation 
Act, was vacated by a decision issued by the U.S. Court of Appeals for 
the Second Circuit in August 2003. This NPRM, which is consistent with 
the Court's decision, proposes to require installation in new light 
vehicles of a tire pressure monitoring system capable of four-tire, 25-
percent under-inflation detection. This proposed rule differs from the 
final rule also in that it tentatively responds to issues raised in 
petitions for reconsideration of the June 2002 final rule and proposes 
to require a TPMS malfunction indicator.

DATES: Comments must be received on or before November 15, 2004.

ADDRESSES: You may submit comments identified by DOT DMS Docket Number 
NHTSA 2004-19054 by any of the following methods:
     Web site: http://dms.dot.gov. Follow the instructions for 
submitting comments on the DOT electronic docket site.
     Fax: 1-202-493-2251.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-001.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal Holidays.
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the online instructions for submitting 
comments.
    Instructions: All submissions must include the agency name and 
docket number or Regulatory Identification Number (RIN) for this 
rulemaking. For detailed instructions on submitting comments and 
additional information on the rulemaking process, see the Public 
Participation heading of the Supplementary Information section of this 
document. Note that all comments received will be posted without change 
to http://dms.dot.gov, including any personal information provided. 
Please see the Privacy Act heading under Rulemaking Analyses and Notice 
regarding documents submitted to the agency's dockets.
    Docket: For access to the docket to read background documents or 
comments received, go to http://dms.dot.gov at any time or to Room PL-
401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal Holidays.

FOR FURTHER INFORMATION CONTACT: For non-legal issues, you may call Mr. 
George Soodoo or Mr. Samuel Daniel, Office of Crash Avoidance Standards 
(Telephone: 202-366-2720) (Fax: 202-366-4329).
    For legal issues, you may call Mr. Eric Stas, Office of Chief 
Counsel (Telephone: 202-366-2992) (Fax: 202-366-3820).
    You may send mail to these officials at National Highway Traffic 
Safety Administration, 400 Seventh Street, SW., Washington, DC 20590.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Executive Summary
II. Background
    A. The TREAD Act
    B. The June 2002 Final Rule Requiring TPMSs
    1. The Notice of Proposed Rulemaking
    2. The Preliminary Determination About the Final Rule
    3. OMB Return Letter
    4. Highlights of the June 2002 Final Rule
    C. Petitions for Reconsideration of the June 2002 Final Rule
    D. The Court of Appeals' Opinion
III. The Proposed Rule
    A. Requirement for Four-Tire, 25-Percent Under-Inflation 
Detection
    B. Lead Time and Phase-In
    C. Responses to Issues Raised in Petitions for Reconsideration
    1. Replacement Tires
    a. TPMS Malfunction Indicator
    b. Owner's Manual Requirements Related to Replacement Tires and 
the TPMS Malfunction Indicator
    2. Spare Tires
    3. Low Tire Pressure Telltale
    4. Test Procedures
    5. System Disablement
    6. Instruction Manuals and Public Awareness Efforts
    7. Reserve Load
    8. Temperature-Corrected Inflation Pressure
    9. Standardization of TPMS Parts
    10. Definitions
    11. Alternative Systems
IV. Benefits
V. Costs
VI. Regulatory Alternatives
VII. Public Participation
VIII. Rulemaking Analyses and Notices

I. Executive Summary

Court Decision and Agency Response

    In August 2003, the U.S. Court of Appeals for the Second Circuit 
(Second Circuit) vacated Federal Motor Vehicle Safety Standard (FMVSS) 
No. 138, Tire Pressure Monitoring Systems, which NHTSA had established 
by a final rule published in the Federal Register on June 5, 2002 (67 
FR 38704). The rule required the installation of tire pressure 
monitoring systems (TPMSs) in light vehicles, thereby implementing a 
mandate in the Transportation Recall Enhancement, Accountability, and 
Documentation (TREAD) Act of 2000 for a rulemaking to require systems 
that warn consumers when a tire is significantly under-inflated.
    The vacated standard covered an initial period from November 1, 
2003 to October 31, 2006. Two compliance options were established for 
this time period. Under the first option, a vehicle's TPMS would have 
been required to warn the driver when the pressure in any single tire 
or in each tire in any combination of tires, up to a total of four 
tires, had fallen to 25 percent or more below the vehicle 
manufacturer's recommended cold inflation pressure for the tires, or a 
minimum level of pressure specified in the standard, whichever pressure 
was higher. Under the second option, a vehicle's TPMS would have been 
required to warn the driver when the pressure in any single tire had 
fallen to 30 percent or more below the vehicle manufacturer's 
recommended cold inflation pressure for the tires, or a minimum level 
of pressure specified in the standard, whichever pressure was higher.
    The agency stated in the document published in June 2002 that it 
planned to issue the second part of the final rule by March 1, 2005. 
The second phase was to establish performance requirements for the 
period beginning on November 1, 2006. In the meantime, NHTSA planned to 
leave the rulemaking docket open for the submission of new data and 
analyses concerning the performance of TPMSs. NHTSA also decided to 
conduct a study of real world performance of vehicles

[[Page 55897]]

equipped with TPMSs, which was nearly completed by the summer of 2003.
    After issuance of the June 2002 final rule, three organizations 
filed suit to challenge the TPMS regulation (FMVSS No. 138), in a case 
before the U.S. Court of Appeals for the Second Circuit. The Second 
Circuit issued its opinion in Public Citizen, Inc. v. Mineta) \1\ on 
August 6, 2003.
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    \1\ 340 F.3d 39 (2d Cir. 2003).
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    The Court held that the agency's inclusion in the standard of a 
one-tire, 30-percent compliance option was contrary to the intent of 
Congress expressed in the TREAD Act. The Court found that that Act 
unambiguously mandates TPMSs capable of monitoring each tire up to a 
total of four tires, effectively precluding that option or any similar 
option with less than a four-tire detection capability. While noting 
that the agency must, as a general matter, consider the reasonableness 
of cost in rulemaking regarding Federal motor vehicle safety standards, 
the court also held that including the one-tire, 30-percent requirement 
as an option was arbitrary and capricious under the Administrative 
Procedure Act, given that the one-tire, 30-percent requirement was less 
cost effective and that the agency did not sufficiently ``explain why 
the costs saved were worth the benefits sacrificed.'' However, the 
Court upheld the agency's use of a phase-in to implement the standard's 
requirements and found that the agency had justification for adopting a 
four-tire, 25-percent option instead of the four-tire, 20-percent 
option proposed at an earlier stage of the rulemaking.
    Consistent with the Second Circuit's opinion, NHTSA is proposing a 
new FMVSS No. 138 that would include a requirement for four-tire, 25-
percent under-inflation detection. Most of the proposed standard's key 
provisions and underlying reasoning remain the same as in the June 2002 
final rule, with the obvious exception of the one-tire, 30-percent 
option, which has been eliminated. In proposing this standard with its 
performance requirement, NHTSA reiterates its intention to adopt a 
standard that is technology-neutral and accommodates future 
technological innovation.
    We note that, if adopted, the approach outlined in this NPRM would 
result in a consolidation of the rulemaking process, because, in light 
of the Court's decision, it is no longer necessary to conduct Part II 
of the rulemaking to determine longer-term compliance requirements 
after October 31, 2006. Similarly, NHTSA also decided to terminate its 
tire pressure survey designed to compare vehicles with direct and 
indirect TPMSs to other vehicles without a TPMS. Under the 
circumstances, the study's findings are no longer needed to help 
determine an appropriate detection level.
    Originally, the phase-in period for the TPMS standard was scheduled 
to begin as of November 1, 2003. However, because the Court vacated the 
standard in its entirety, the agency must promulgate an updated final 
rule before a phase-in can commence. To determine the extent to which 
vehicle manufacturers must alter pre-vacation product plans to comply 
with the new final rule, the agency required all major automobile 
manufacturers and TPMS suppliers to respond to Special Orders it issued 
on September 9, 2003 (issued pursuant to 49 U.S.C. 30166(g)(1) and 49 
CFR 510).\2\ This NPRM proposes to establish a new phase-in schedule, 
accounting for these changed circumstances.
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    \2\ In comments submitted to the Office of Management and Budget 
related to the agency's Special Order, the Alliance of Automobile 
Manufacturers (Alliance) suggested that its members' product plans 
were predicated on the agency's amending the final rule in a manner 
acceptable to its members (see Docket No. NHTSA-2000-8572-277). 
Specifically, the Alliance in its September 5, 2003 letter stated, 
``It is important to note that those plans were predicated on the 
assumption that the major issues raised by the Alliance in its July 
22, 2002 petition for reconsideration (with supplement on October 
30, 2002) and its April 29, 2003 petition for rulemaking (with 
supplement on June 30, 2003) of FMVSS 138 would be satisfactorily 
resolved'' (emphasis in original). This expectation was repeated in 
several vehicle manufacturer responses to the Special Order.
    We believe that a clarification of the regulatory process is in 
order. NHTSA carefully considers petitions for reconsideration of 
final rules that raise new issues arising from resolution of matters 
addressed in response to rulemaking proposals. After careful review, 
the agency decides whether to grant the petitions and whether to 
modify the rule. In any event, NHTSA's response to such petitions is 
prospective. In the interim, the final rule remains effective as 
originally promulgated. Because manufacturers cannot assume that 
requested changes will be made in response to such petitions, they 
must plan to comply with the final rule as issued, without 
reservation. At the same time, the agency recognizes its 
responsibility to grant or deny petitions for reconsideration of its 
rules in a timely fashion.
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    NHTSA is proposing the following phase-in schedule: 50 percent of a 
vehicle manufacturer's light vehicles would be required to comply with 
the standard during the first year (September 1, 2005 to August 31, 
2006); 90 percent during the second year (September 1, 2006 to August 
31, 2007); all light vehicles thereafter. This proposal would permit 
carry-forward credits for vehicles certified as complying with the 
standard that are produced after the effective date of the final rule.
    As part of this NPRM, we also are addressing various issues raised 
in petitions for reconsideration of the June 2002 final rule. At the 
time of the Court's decision, the agency was nearing publication of its 
responses to the petitions, and the majority of those issues remain 
relevant to this updated TPMS rulemaking. Thus, we have decided to 
address them here. Accordingly, we have proposed some modifications, as 
compared to the vacated rule. These matters are discussed in further 
detail below.

Response to Issues Raised in Petitions for Reconsideration

    Petitions for reconsideration of the June 2002 final rule raised a 
variety of issues, the more significant of them involving the 
standard's requirement that a vehicle's TPMS must work with all 
replacement tires of the tire size(s) authorized or recommended by the 
vehicle's manufacturer. Concerns were expressed that the requirement 
was overly broad and that some tire designs will prevent the proper 
functioning of the TPMS. The petitions also provided information 
indicating that there are as many as 600 tire models that could be used 
as replacements on some vehicle models.
    After considering the arguments raised in the petitions and the 
supplemental information on TPMS compatibility with replacement tires, 
we have tentatively decided to alter our approach to this topic. 
Specifically, we are proposing only to require vehicle manufacturers to 
assure compliance with FMVSS No. 138 with the tires installed on the 
vehicle at the time of initial sale. We have tentatively decided upon 
this approach for the following reasons.
    First, information presented to NHTSA in the petitions shows that 
there are currently over four million TPMS-equipped vehicles,\3\ and 
neither the agency nor vehicle manufacturers have received reports 
indicating any significant performance problems with those TPMSs when 
replacement tires are installed on the vehicle. Further, there are a 
variety of aftermarket TPMSs, and again, there has not been any 
significant number of reports of incompatibility problems between those 
systems and replacement tires. Thus, this significant real world 
population suggests that TPMSs are expected to

[[Page 55898]]

continue to work with replacement tires in the vast majority of cases.
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    \3\ Letter from Robert Strassburger, Vice President, Alliance of 
Automobile Manufacturers, to NHTSA (October 20, 2003) (Docket No. 
NHTSA-2000-8572-277).
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    However, NHTSA has been presented with data demonstrating that a 
very small number of replacement tires may cause a vehicle's TPMS to 
exhibit functional problems for which there is currently no clear 
solution. The identified problems are primarily related to the tires' 
construction (e.g., run-flat tires) and material content (e.g., high 
carbon content in low aspect-ratio tires, thicker sidewall, or steel 
body ply sidewall).
    In many instances, TPMSs may function properly even when equipped 
with replacement tires with the above-mentioned characteristics, but to 
date, it has not been possible to develop an appropriate performance 
measure that would reliably identify those anomalous tires that would 
prevent proper TPMS functioning. However, available data show that, in 
2002, light vehicle tires having either steel body ply cords (steel 
casing tires) or run-flat capability accounted for less than 0.5 
percent of tires distributed in the United States.\4\
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    \4\ Letter from Steven Butcher, Vice President, Rubber 
Manufacturers Association, to NHTSA (October 31, 2003) (Docket No. 
NHTSA-2000-8572-282).
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    Based upon the above new information, we now believe that there is 
not a sufficient basis to require vehicle manufacturers to assure 
compliance with all replacement tires. While the number of tires 
expected to be incompatible with a given TPMS is expected to be small, 
such a requirement would nonetheless raise significant practicability 
concerns. For example, vehicle manufacturers will not be able to 
anticipate future tire construction changes; therefore, a replacement 
tire requirement similar to the one contained in the June 2002 final 
rule could force vehicle manufacturers to halt vehicle sales over a 
problem they could not correct. We continue to believe, however, that 
the TPMS should continue to function properly beyond the point at which 
the vehicle's original tires are replaced, a clearly foreseeable event. 
At a minimum, consumers need to know if the TPMS is not functioning 
with the replacement tires. Otherwise, an unilluminated low tire 
pressure telltale would give consumers a false sense of security in 
those cases.
    The Alliance has recommended a framework for resolution of the 
problem of incompatible replacement tires, predicated upon a 
requirement for a TPMS malfunction indicator coupled with a related 
statement in the vehicle's owner's manual.\5\ We believe that this 
approach could provide not only a relatively low-cost solution to the 
replacement tire incompatibility problem, but also additional warnings 
regarding other types of TPMS malfunctions (e.g., sensor damage, signal 
attenuation, and dead batteries).
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    \5\ Letter from Vann Wilber, Vehicle Safety and Harmonization 
Director, Alliance of Automobile Manufacturers, to NHTSA (December 
9, 2003) (Docket No. NHTSA-2000-8572-285).
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    Therefore, in this NPRM, we are proposing to require the TPMS to be 
equipped with a telltale that would alert the driver of a TPMS 
malfunction, tire-related or otherwise. We are proposing that the 
malfunction warning be provided either through a separate, dedicated 
telltale or through a distinctive warning delivered by the low tire 
pressure telltale.
    In addition, we are proposing to require that the owner's manual 
include a statement that would make consumers aware of this potential 
problem. Specifically, we are proposing to require vehicle 
manufacturers to alert consumers regarding: (1) Potential problems 
related to compatibility between the vehicle's TPMS and various types 
of replacement tires, and (2) the presence and operation of the TPMS 
malfunction indicator.
    Manufacturers also asked the agency to provide greater specificity 
in the TPMS test procedures in order to increase objectivity. After 
consideration of these recommendations, we are proposing to make the 
standard's test procedures more specific. However, we also seek to 
ensure that the test procedures continue to be broad enough to 
replicate a range of real world driving conditions, rather than 
encourage development of systems that are designed and tested for 
effectiveness only in a narrow set of driving circumstances. 
Specifically, we are proposing to designate a course for compliance 
testing (i.e., the Southern Loop of the Treadwear Test Course), which 
is both objective and representative of a range of driving conditions. 
In addition, we are proposing to refine the calibration and system 
detection provisions to specify that driving times in the designated 
speed range will be cumulative (not continuous) and that system 
calibration or low tire detection time will not accumulate during 
periods when the brake is applied. Further, we also are proposing to 
specify that the vehicle's tires will be shaded from direct sun when 
parked. We believe that the proposed modifications would sufficiently 
address calls for greater specificity in the standard's test 
procedures, while ensuring that the TPMS will function on a variety of 
roadways and road conditions.
    In response to other issues raised in the petitions, we are 
proposing to incorporate additional changes in this NPRM, including 
revision of the definition of ``small volume manufacturer'' and 
clarification of specific issues that may arise under FMVSS No. 138.

II. Background

A. The TREAD Act

    Congress enacted the TREAD Act; \6\ on November 1, 2000. Section 13 
of that Act \7\ required the Secretary of Transportation, within one 
year of the statute's enactment, to complete a rulemaking ``to require 
a warning system in new motor vehicles to indicate to the operator when 
a tire is significantly under inflated.'' Section 13 also required the 
regulation to take effect within two years of the completion of the 
rulemaking. Responsibility for this rulemaking was delegated to NHTSA.
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    \6\ Public Law 106-414, 114 Stat. 1800 (2000).
    \7\ See 49 U.S.C. Sec.  30123 note (2003).
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B. The June 2002 Final Rule Requiring TPMSs

1. The Notice of Proposed Rulemaking
    NHTSA initiated the TPMS rulemaking with the publication of a 
Notice of Proposed Rulemaking (NPRM) on July 26, 2001 (see 66 FR 38982, 
Docket No. NHTSA-2000-8572-30). That NPRM proposed to require passenger 
cars, light trucks, multipurpose passenger vehicles, and buses with a 
gross vehicle weight rating of 10,000 pounds or less, except those with 
dual wheels on an axle, to be equipped with a TPMS.
    The agency sought comment on two alternative sets of performance 
requirements for TPMSs and indicated that it contemplated adopting only 
one of them in the final rule. The first alternative would have 
required that the driver be warned when the pressure in any single tire 
or in each tire in any combination of tires, up to a total of four 
tires, had fallen to 20 percent or more below the vehicle 
manufacturer's recommended cold inflation pressure for the vehicle's 
tires (the placard pressure), or a minimum level of pressure specified 
in the standard, whichever was higher. (This alternative is referred to 
below as the four-tire, 20-percent alternative.) The second alternative 
would have required that the driver be warned when the pressure in any 
single tire or in each tire in any combination of tires, up to a total 
of

[[Page 55899]]

three tires, had fallen to 25 percent or more below the placard 
pressure, or a minimum level of pressure specified in the standard, 
whichever was higher. (This alternative is referred to below as the 
three-tire, 25-percent alternative.)
    There are two types of TPMSs currently available, direct TPMSs and 
indirect TPMSs.\8\ Direct TPMSs have a pressure sensor in each wheel 
that transmit pressure information to a receiver. In contrast, indirect 
TPMSs do not have tire pressure sensors, but instead rely on the wheel 
speed sensors, typically a component of an anti-lock braking system 
(ABS), to detect and compare differences in the rotational speed of a 
vehicle's wheels, which correlate to differences in tire pressure.
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    \8\ We anticipate that new types of TPMS technology may be 
developed in the future that will be capable of meeting the NPRM's 
proposed requirements. For example, such systems might incorporate 
aspects of both direct and indirect TPMS (i.e., hybrid systems). In 
concert with TPMS suppliers, tire manufacturers might be able to 
incorporate TPMS sensors directly into the tires themselves. In 
proposing a performance standard, NHTSA is cognizant of and seeks to 
encourage technological innovation.
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    To meet the four-tire, 20-percent alternative within the timeframe 
envisioned in the NPRM, vehicle manufacturers likely would have had to 
install direct TPMSs because it is unlikely that even improved indirect 
systems would be able to detect loss of pressure until pressure has 
fallen 25 percent and to detect all combinations of significantly 
under-inflated tires. To meet the three-tire, 25-percent alternative, 
vehicle manufacturers would have been able to install either direct 
TPMSs or improved indirect TPMSs.
2. The Preliminary Determination About the Final Rule
    After consideration of the comments submitted in response to the 
NPRM, NHTSA preliminarily determined to issue a final rule that would 
have specified a four-year phase-in schedule and that would have 
allowed compliance with either of two options during the phase-in 
period (i.e., between November 1, 2003 and October 31, 2006). Under the 
first option, a vehicle's TPMS would have had to warn the driver when 
the pressure in one or more of the vehicle's tires, up to a total of 
four tires, was 25 percent or more below the placard pressure, or a 
minimum level of pressure specified in the standard, whichever pressure 
was higher. (This option is referred to below as the four-tire, 25-
percent option.) Under the second option, a vehicle's TPMS would have 
had to warn the driver when the pressure in any one of the vehicle's 
tires was 30 percent or more below the placard pressure, or a minimum 
level of pressure specified in the standard, whichever pressure was 
higher. (This option is referred to below as the one-tire, 30-percent 
option.) The minimum levels of pressure specified in the standard were 
the same for both compliance options.
    After the phase-in (i.e., after October 31, 2006), the second 
option would have been terminated, and the provisions of the first 
option would have become mandatory for all new vehicles. Thus, all 
vehicles would have been required to meet a four-tire, 25-percent 
requirement.
3. OMB Return Letter
    After reviewing the draft final rule, OMB returned it to NHTSA for 
reconsideration, with a letter explaining its reasons for doing so, on 
February 12, 2002. For a discussion of that letter and NHTSA's analysis 
of the issues it raised, see NHTSA's June 5, 2002 final rule at 67 FR 
38704, 38712, 38718-22.
4. Highlights of the June 2002 Final Rule
    Consistent with the OMB return letter, the agency divided the TPMS 
final rule into two parts because it decided to defer its decision as 
to which long-term performance requirements for TPMS would best satisfy 
the mandate of the TREAD Act. This deferral was intended to allow the 
agency to consider additional data on the effect and performance of 
TPMSs currently in use.
    The first part of the final rule was published in the Federal 
Register on June 5, 2002 (67 FR 38704) (Docket No. NHTSA 2000-8572). It 
established requirements for vehicles manufactured during the first 
three years (i.e., between November 1, 2003 and October 31, 2006) and 
phased TPMSs in by increasing percentages of production. The agency 
stated that the second part of the final rule would establish 
requirements for vehicles manufactured on or after November 1, 2006.
a. Part One--November 2003 Through October 31, 2006
    The June 2002 final rule provided two compliance options during the 
interim period. Under the first compliance option, vehicle 
manufacturers would have been required to equip their light vehicles 
(i.e., those with a GVWR of 4,536 kg (10,000 pounds) or less) with 
TPMSs to warn the driver when the pressure in any single tire or in 
each tire in any combination of tires, up to a total of four tires, is 
25 percent or more below the vehicle manufacturer's recommended cold 
inflation pressure for the tires, or a minimum level of pressure 
specified in the standard, whichever pressure is higher. Under the 
second compliance option, the vehicle's TPMS would have been required 
to warn the driver when the pressure in any single tire is 30 percent 
or more below the vehicle manufacturer's recommended cold inflation 
pressure for the tires, or a minimum level of pressure specified in the 
standard, whichever pressure is higher.\9\
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    \9\ The minimum levels of pressure were the same for both 
compliance options.
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    The two compliance options were outgrowths of the alternative sets 
of requirements proposed in the NPRM. In response to comments 
indicating that current indirect TPMSs could not meet the proposed 
three-tire, 25-percent under-inflation requirements, the agency adopted 
the one-tire, 30-percent option. That option would have allowed those 
systems to be used during the phase-in. The four-tire, 25-percent 
under-inflation option could have been met by installing either direct 
TPMSs or hybrid TPMSs (i.e., TPMSs that combine direct and indirect 
TPMS technologies). One TPMS supplier indicated the potential for 
developing and producing hybrid systems, although it also indicated 
that it did not currently have plans for doing so.
    The owner's manual for vehicles certified to either compliance 
option would have been required to include an explanation of the 
purpose of the yellow low tire pressure warning telltale, the potential 
consequences of driving on significantly under-inflated tires, the 
meaning of the telltale when it is illuminated, and the actions that 
drivers should take in response.
    To facilitate compliance with the options, the rule included a 
phase-in of the standard's requirements by increasing percentages of 
production. Ten percent of a vehicle manufacturer's light vehicles were 
to be required to comply with either compliance option during the first 
year (November 1, 2003 to October 31, 2004), 35 percent during the 
second year (November 1, 2004 to October 31, 2005), and 65 percent 
during the third year (November 1, 2005 to October 31, 2006). The 
agency permitted carry-forward credits for vehicles that were 
manufactured during the phase-in and equipped with TPMSs that comply 
with the four-tire, 25-percent option.
    NHTSA also provided in the June 2002 final rule that small volume 
manufacturers would be given to the end of the phase-in period to 
comply with the TPMS requirements. Later, similar treatment was 
accorded to final stage manufacturers and alterers through a correcting 
amendment to the

[[Page 55900]]

final rule published in the Federal Register.\10\ As with previous 
phase-ins, NHTSA adopted reporting requirements to aid it in monitoring 
the implementation of the phase-in. The agency included these reporting 
requirements in 49 CFR Part 590.
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    \10\ 68 FR 4107 (January 28, 2003).
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b. Part Two--November 2006 and Thereafter
    The June 2002 final rule provided that beginning November 1, 2006, 
all covered vehicles would be required to comply with the requirements 
in the second part of the final rule. The agency stated its intention 
to publish the second part of the final rule by March 1, 2005, in order 
to provide sufficient lead time to manufacturers.
    In anticipation of making its decision about long-term 
requirements, the agency left the rulemaking docket open for the 
submission of new data and analyses. The agency also committed to 
conduct and place in the docket a tire pressure survey comparing the 
tire pressures of vehicles without any TPMS to the pressure of vehicles 
with TPMSs not complying with the four-tire, 25-percent performance 
option. After consideration of the rulemaking record, as supplemented 
by the tire pressure study and any other new information submitted to 
the agency, NHTSA would issue the second part of the rule.
    Based upon the record before the agency at the time of publication 
of the first part of the final rule, NHTSA stated its tentative belief 
that the four-tire, 25-percent option would best meet the mandate in 
the TREAD Act. However, NHTSA remained open to the possibility of 
obtaining or receiving new information sufficient to justify a 
continuation of the compliance options established by the first part of 
the final rule, or the adoption of some other alternative.

C. Petitions for Reconsideration of the June 2002 Final Rule

    NHTSA received thirteen petitions for reconsideration of the June 
5, 2002 final rule from: (1) Ferrari S.p.A.; (2) Delphi Auto, Inc. 
(Delphi); (3) Japan Automobile Tyre Manufacturers Association, Inc. 
(JATMA); (4) Johnson Controls, Inc.; (5) Volkswagen of America, Inc. 
(Volkswagen); (6) Bureau de Normalisation de l'Automobile (BNA) ISO/
TC22; (7) Porsche Cars North America, Inc. (Porsche); (8) Alliance of 
Automobile Manufacturers (Alliance); (9) Rubber Manufacturers 
Association (RMA); (10) Aviation Upgrade Technologies; (11) Vehicle 
Services Consulting, Inc. (VSC); (12) DENSO International America, Inc. 
(DENSO); and (13) Maserati S.p.A.
    The petitioners raised a variety of issues, including ones related 
to the rule's requirements for functioning of the TPMS with replacement 
tires, system calibration, tire reserve load, the compliance testing 
procedures, system disablement and reset, the TPMS telltale (e.g., 
issues related to color, extinguishment time, reconfigurable displays, 
and bulb check), definitions, alternative systems, and policy and 
procedures for the second part of the rulemaking.
    NHTSA was in the process of finalizing its responses to the various 
petitions for reconsideration at the time of the Second Circuit's 
decision. However, because the majority of the issues raised in the 
petitions for reconsideration remain relevant, we have decided to 
address them substantively in this proposed rule.

D. The Court of Appeals' Opinion

    After issuance of the June 2002 final rule, Public Citizen, Inc., 
New York Public Interest Research Group, and the Center for Auto Safety 
filed a suit challenging certain aspects of the TPMS regulation.
    The Second Circuit issued its opinion in Public Citizen, Inc. v. 
Mineta on August 6, 2003, which held that the agency's adoption in the 
standard of a one-tire, 30-percent compliance option is ``contrary to 
the intent of the TREAD Act and, in light of the relative shortcomings 
of indirect systems, arbitrary and capricious.'' \11\ The Court found 
that the TREAD Act unambiguously mandates TPMSs capable of monitoring 
each tire, up to a total of four tires, effectively precluding the one-
tire, 30-percent option, or any similar option that cannot detect 
under-inflation in any combination of tires up to four tires.
---------------------------------------------------------------------------

    \11\ 340 F.3d 39, 54 (2d Cir. 2003).
---------------------------------------------------------------------------

    The Court concluded that, against a backdrop of more efficacious 
performance of direct systems, current indirect systems (i.e., those 
unable to meet a four-tire, 25-percent standard) are not sufficiently 
effective as would permit NHTSA to allow automakers to install those 
indirect systems in new motor vehicles.\12\ The court opinion went on 
to note that the record, as reflected in NHTSA's final rule, suggested 
that the four-tire, 25-percent option would not only prevent more 
injuries and save more lives, but also that it would be more cost-
effective on a per-life, per-injury basis than adopting both options 
together.
---------------------------------------------------------------------------

    \12\ The Court found that given current technological 
limitations, indirect systems cannot meet the requirements of the 
four-tire, 25-percent under-inflation option under the June 2002 
final rule, and even under the one-tire, 30-percent compliance 
option, indirect systems cannot detect low tire pressure in all 
cases (e.g., when two tires on the same side of the vehicle or on 
the same axle are under-inflated, or when all four tires are equally 
under-inflated).
---------------------------------------------------------------------------

    However, the Court stated that the agency was correct to consider 
the relative costs of adopting or rejecting different compliance 
options. Further, the Court did not preclude the use of indirect 
systems, to the extent that they are able to meet the performance 
requirements proposed in this NPRM. This point is noteworthy because it 
is NHTSA's practice to issue performance standards that seek to give 
manufacturers as broad a choice as possible in selecting the technology 
to be used in meeting those standards. Thus, as TPMS technology 
develops, it may become possible for new types of systems to meet the 
proposed performance requirements.
    In all of the other areas of challenge, the Court supported the 
agency's actions. Specifically, the Court upheld NHTSA's use of a 
phase-in as part of the TPMS final rule. The Court also held that 
NHTSA's decision not to adopt the four-tire, 20-percent compliance 
option proposed in the NPRM was not arbitrary and capricious. The Court 
found that the agency had explained adequately that the four-tire, 25-
percent option may permit improved indirect TPMSs and hybrid TPMSs to 
be used to comply with the standard and that this option was 
substantially more cost-effective than the proposed four-tire, 20-
percent option.
    Ultimately, the Court vacated the rule (FMVSS No. 138) in its 
entirety and directed the agency to issue a new rule consistent with 
its August 6, 2003 opinion. NHTSA published a final rule in the Federal 
Register on November 20, 2003, vacating FMVSS No. 138. The agency 
stated that, at present, vehicle manufacturer have no certification or 
reporting responsibilities. 68 FR 65404.

III. The Proposed Rule

A. Requirement for Four-Tire, 25-Percent Under-Inflation Detection

    This NPRM proposes to re-establish FMVSS No. 138, Tire Pressure 
Monitoring System, in a manner consistent with the Second Circuit's 
opinion. Specifically, it proposes to require passenger cars, 
multipurpose passenger vehicles, trucks, and buses with a GVWR of 4,536 
kg (10,000 pounds) or less, except those with dual wheels on an axle, 
to be equipped with a TPMS to alert the driver when one or more of the 
vehicle's tires, up to all four

[[Page 55901]]

of its tires, are significantly under-inflated. The rule proposes 
requirements for covered vehicles manufactured on or after September 1, 
2005 (i.e., Model Year (MY) 2006), subject to the proposed phase-in 
schedule discussed below. The proposed standard is intended to be 
technology-neutral so as to permit compliance with any available TPMS 
technology that meets the performance requirements.
    Because the Second Circuit vacated the entire TPMS standard in 
striking down the one-tire, 30-percent option, it is necessary for 
NHTSA again to propose the complete regulatory text for FMVSS No. 138. 
The following points highlight the key provisions of the proposed 
requirements.
     The TPMS would be required to warn the driver when the 
pressure in one or more of the vehicle's tires, up to a total of four 
tires, is 25 percent or more below the vehicle manufacturer's 
recommended cold inflation pressure for the tires, or a minimum level 
of pressure specified in the standard, whichever pressure is 
higher.\13\
---------------------------------------------------------------------------

    \13\ As proposed, these minimum activations pressures (MAPs) are 
included in Table 1 of the standard, which is identical to the Table 
1 that appeared in the June 5, 2002 final rule. However, we note 
that the Alliance submitted a Petition for Rulemaking on April 29, 
2003 that asks NHTSA to make certain changes to the minimum 
activation pressures in Table 1 (Docket No. NHTSA-2000-8572-265). 
NHTSA is in the process of evaluating the issues raised in the 
Alliance petition.
---------------------------------------------------------------------------

     Vehicle manufacturers would be required to certify vehicle 
compliance under the standard with the tires installed on the vehicle 
at the time of initial vehicle sale.\14\
---------------------------------------------------------------------------

    \14\ We note that some vehicle manufacturers authorize their 
dealers to replace the vehicle's factory-installed tires with other 
tires, including ones with a different size and/or recommended cold 
tire inflation pressure. The TPMS would have to perform properly 
with any such tires, because the vehicle could be equipped with 
those tires at the time of initial sale. Of course, the manufacturer 
would not have that responsibility if the dealer installed other 
tires without manufacturer authorization. However, the dealer would 
violate the Motor Vehicle Safety Act if it installed tires on a new 
vehicle that prevented the TPMS from functioning properly. See 49 
U.S.C. 30112(a).
---------------------------------------------------------------------------

     The TPMS would be required to include a low tire pressure-
warning telltale \15\ (yellow) that must remain illuminated as long as 
any of the vehicle's tires remains significantly under-inflated and the 
vehicle's ignition locking system is in the ``On'' (``Run'') position. 
The telltale must be extinguished when all of the vehicle's tires cease 
to be significantly under-inflated.\16\ The TPMS's low tire pressure-
warning telltale would be required to perform a bulb-check at vehicle 
start-up.
---------------------------------------------------------------------------

    \15\ As part of this notice proposing to re-establish FMVSS No. 
138, we are proposing to add two versions of the TPMS low tire 
pressure telltale and a TPMS malfunction telltale to Table 2 of 
FMVSS No. 101, Controls and Displays. The proposed regulatory text 
in this NPRM incorporates the TPMS telltales in Table 2, as that 
table currently exists in the Code of Federal Regulations. However, 
we note that NHTSA published an NPRM in the Federal Register on 
September 23, 2003 that proposes to update and expand FMVSS No. 101 
(68 FR 55217). Publication of the present version of Table 2 here is 
not intended to suggest a change in approach to the ongoing FMVSS 
No. 101 rulemaking. We anticipate that the TPMS telltales would be 
incorporated in a revised Table 2, once a final decision is reached 
on updating Standard No. 101.
    \16\ For some systems, extinguishment may occur automatically 
upon re-inflation of the tires to the proper pressure. Other systems 
may require manual reset in accordance with the vehicle 
manufacturer's instructions. However, manual reset of the system may 
not result in extinguishment of the low tire pressure telltale prior 
to correction of the under-inflation situation.
---------------------------------------------------------------------------

     The TPMS also would be required to include a malfunction 
indicator to alert the driver when the system is non-operational, and 
thus unable to provide the required low tire pressure warning. We are 
proposing that TPMS malfunction could be indicated by either:
    (1) Installing a separate, dedicated telltale (yellow) that 
illuminates upon detection of the malfunction and remains continuously 
illuminated as long as the ignition locking system is in the ``On'' 
(``Run'') position and the situation causing the malfunction remains 
uncorrected, or
    (2) Designing the low tire pressure telltale so that it flashes for 
one minute when a malfunction is detected, after which the telltale 
would remain illuminated as long as the ignition locking system is in 
the ``On'' (``Run'') position. This flashing and illumination sequence 
would be repeated upon each subsequent vehicle start-up until the 
situation causing the malfunction has been corrected.
    If the option for a separate telltale is selected, the TPMS 
malfunction telltale would be required to perform a bulb-check at 
vehicle start-up.
     The TPMS would not be required to monitor the spare tire 
(if provided), either when it is stowed or when it is installed on the 
vehicle.
     For vehicles certified under the standard, vehicle 
manufacturers would be required to provide in the owner's manual an 
explanation of the purpose of the low tire pressure warning telltale, 
the potential consequences of significantly under-inflated tires, the 
meaning of the telltale when it is illuminated, and what actions 
drivers should take when the telltale is illuminated. Vehicle 
manufacturers also would be required to provide a specified statement 
in the owner's manual regarding: (1) Potential problems related to 
compatibility between the vehicle's TPMS and various replacement tires, 
and (2) the presence and operation of the TPMS malfunction indicator.

B. Lead Time and Phase-In

    The Second Circuit decision vacating FMVSS No. 138, while affirming 
the use of a phase-in as part of the TPMS rulemaking, necessitates a 
change in the phase-in schedule in order to ensure the practicability 
of the standard's implementation. First, for those vehicle 
manufacturers that had intended to certify to the June 5, 2002 final 
rule's one-tire, 30-percent option, redesign and a change in production 
plans may be necessary in order to meet the proposed four-tire, 25-
percent detection requirements of this NPRM. Second, there must be an 
adequate supply of TPMSs available that meet the proposed requirements 
of the standard so that vehicle manufacturers would be capable of 
meeting the phase-in requirements.
    To help determine appropriate lead time and phase-in percentages, 
NHTSA issued a number of Special Orders on September 9, 2003. NHTSA 
issued Special Orders to 14 vehicle manufacturers to ascertain what 
their production plans had been for compliance with the June 2002 final 
rule, including the option(s) under which they intended to certify and 
the technologies they intended to use in doing so. NHTSA also issued 
Special Orders to 13 TPMS suppliers in order to determine their current 
and planned production, as well as their current capacity and their 
ability to produce beyond their current capacity. The majority of the 
information submitted pursuant to these Special Orders is confidential 
business information (CBI) under the relevant NHTSA regulation.\17\ We 
believe that the information obtained in response to these Special 
Orders provides the agency with the necessary data to propose and 
ultimately set a fair and reasonable phase-in schedule.
---------------------------------------------------------------------------

    \17\ 49 CFR Part 512 (as amended, 68 FR 44209 (July 28, 2003)).
---------------------------------------------------------------------------

    From the responses to these Special Orders, NHTSA learned that, in 
anticipation of the start of the phase-in under the June 2002 final 
rule, most vehicle manufacturers were moving aggressively toward 
installation of TPMSs capable of meeting the four-tire, 25-percent 
detection requirement, but some were not. The information provided by 
TPMS suppliers indicated sufficient capacity to supply TPMSs with a 
four-tire, 25-percent detection capability in quantities that would

[[Page 55902]]

easily meet the newly proposed phase-in requirements.
    Based upon the information obtained from the data submitted in 
response to the Special Orders, NHTSA is proposing to adopt the 
following phase-in schedule: 50 percent of a vehicle manufacturer's 
light vehicles would be required to comply with the standard during the 
first year (September 1, 2005 to August 31, 2006); 90 percent during 
the second year (September 1, 2006 to August 31, 2007); and all 
vehicles thereafter.\18\
---------------------------------------------------------------------------

    \18\ The responses to the Special Orders also contained 
information indicating that a 20% phase-in would be appropriate for 
MY 2005. The agency, however, does not believe the rulemaking 
process will be completed in time to allow for the adoption of a MY 
2005 requirement, so we are not proposing one in this NPRM.
---------------------------------------------------------------------------

    To encourage early compliance, NHTSA is proposing to permit carry-
forward credits for vehicles that are certified as complying with the 
standard \19\ and that are manufactured on or after the effective date 
of the final rule.\20\ However, beginning September 1, 2007, all 
covered vehicles would be required to comply with the standard, without 
regard to any earlier carry-forward credits.
---------------------------------------------------------------------------

    \19\ Any such certification of compliance with the standard is 
irrevocable.
    \20\ The effective date of the amendments made to the Code of 
Federal Regulations by the final rule would likely be specified as 
30 days after the issuance of the final rule.
---------------------------------------------------------------------------

    As before, NHTSA is proposing to exclude from the phase-in 
requirements final stage manufacturers, alterers, and small volume 
manufacturers (SVMs) (although the criteria for designation as an SVM 
has been revised). We also are proposing to maintain the phase-in 
reporting requirements, as modified to reflect the newly proposed 
phase-in schedule.\21\ We request public comment on the schedule that 
NHTSA has proposed.
---------------------------------------------------------------------------

    \21\ Since the issuance of the June 5, 2002 final rule, NHTSA 
has published an unrelated NPRM in the Federal Register that, in 
part, proposes to consolidate the placement of phase-in reporting 
requirements for various standards (including the TPMS standard) in 
a renamed Part 585, Phase-in Reporting Requirements. See 68 FR 46546 
(August 6, 2003). Consequently, in this notice, we are proposing 
ultimately to incorporate the TPMS phase-in reporting requirements 
as Subpart D to Part 585.
---------------------------------------------------------------------------

C. Responses to Issues Raised in Petitions for Reconsideration

    As noted previously, NHTSA was nearing the point of issuing its 
response to petitions for reconsideration of the June 5, 2002 final 
rule for TPMS, when the Second Circuit issued its opinion in Public 
Citizen, Inc. v. Mineta. Most issues raised in the petitions for 
reconsideration were not directly related to the one-tire, 30-percent 
option nullified by the Court and thus remain relevant. Accordingly, 
NHTSA decided to address those issues in this notice, as discussed 
below.
1. Replacement Tires
    As expressed in paragraph S4.4 of the standard, the June 5, 2002 
final rule required that each TPMS-equipped vehicle meet the 
requirements of FMVSS No. 138 when the vehicle's original tires are 
replaced with optional or replacement tires (for simplicity of 
discussion, we refer below to these tires as replacement tires) of the 
size(s) authorized or recommended for use on the vehicle by the vehicle 
manufacturer. Paragraph S6(l) set out test procedure provisions 
applicable to replacement tires.
    TPMS operation with replacement tires was the issue most frequently 
raised and extensively discussed in the petitions for reconsideration. 
Five petitioners (Delphi, DENSO, the Alliance, Johnson Controls, and 
JATMA) raised this issue. The petitioners generally argued that the 
standard's replacement tire requirements are not practicable because 
there are a large number of replacement tires available in the tire 
sizes authorized or recommended for each vehicle model and the 
construction characteristics of some of those tires may prevent proper 
functioning of the TPMS, even within a given size.
    The Delphi petition asked us to amend FMVSS No. 138 S4.4 and S6(l) 
so that manufacturers need only certify TPMS operation with replacement 
tires that are of the same size and ``type'' recommended by the vehicle 
manufacturer. According to Delphi, tire ``type'' is a critical factor 
that will affect TPMS operation, and takes into account properties such 
as construction, speed rating, and manufacturer's brand. Tire 
``construction'' involves the number of plies and the material of the 
plies in both the tread and the sidewall.
    The Delphi petition argued that adding a tire type limitation to 
the requirement for TPMS compliance with replacement tires is 
necessary, not only from a practical standpoint, but in order to render 
the standard objective, as required under the National Traffic and 
Motor Vehicle Safety Act (49 U.S.C. Chapter 301) (Safety Act). The 
Johnson Controls petition argued that the current, above-mentioned 
provisions of the standard related to replacement tires are not 
``reasonable, practicable, and appropriate,'' as required by section 
30111(b)(3) of the Safety Act. It argued that the requirement for TPMS 
compliance with the standard for all replacement tires would go beyond 
the limitations of current TPMS capabilities.
    Delphi argued that lack of specificity regarding the type of tire 
would force manufacturers to anticipate future tire designs in order to 
certify a vehicle under the TPMS rule, rendering the rule insufficient 
to meet the objectivity requirements of the Safety Act. Further, Delphi 
argued that in practical terms, without a tire type limitation, 
manufacturers would have to certify certain TPMS-equipped vehicle 
models for compliance with over 100 replacement tire options, if size 
is the only limiting factor.
    DENSO's petition expressed similar concerns and added that, for 
indirect TPMSs, tire pressure sensitivity (i.e., the relationship 
between tire radius and tire inflation pressure) is a design parameter 
of significant operational importance. However, according to DENSO, 
tire pressure sensitivity varies by tire manufacturer or brand even if 
such tires are of an identical size, thereby making it difficult to 
ensure that a TPMS would be able to comply with the standard for all 
replacement tires of the specified size. According to the petitioner, 
similar concerns apply to direct TPMSs because some aftermarket tires 
are constructed with materials (e.g., steel) that, to varying degrees, 
may shield the radio signal transmitted from the TPMS tire sensor to 
the receiver. The DENSO petition asked NHTSA to limit the universe of 
replacement tires for which manufacturers must certify TPMS 
functionality under FMVSS No. 138 by revising paragraph S4.4 of the 
standard to require vehicle manufacturers to certify TPMS compliance 
only for tires released as original equipment.
    The Alliance petition also objected to the final rule's requirement 
that the TPMS operate properly with all replacement tires. The Alliance 
argued that just because different brands and styles of the same size 
tire meet the same tire industry standards, it does not mean that such 
tires are equivalent in form and function. For example, it argued that 
different tires of the same size are often designed to perform under a 
variety of road and weather conditions, and at varying levels of 
durability, performance, and cost. Thus, according to the petitioner, 
there may be fundamental differences in tire construction, even though 
such tires may meet the same basic performance standards. The Alliance 
also stated in its petition that the current availability of 
aftermarket direct TPMSs does not guarantee that these systems will be 
sensitive to all tire constructions, and

[[Page 55903]]

such problems may be even more pronounced for indirect TPMSs.
    In its petition, the Alliance argued also that the replacement tire 
requirement is not practicable. According to the Alliance, there may be 
hundreds of aftermarket tires of the same size as a vehicle's original 
equipment tires, but in some cases, differences in tire properties may 
pose insurmountable problems for proper functioning of the TPMS. It 
argued that the mere existence of a non-compatible tire would render 
compliance with S4.4 impossible. In addition, because tire 
manufacturing is largely beyond the control of vehicle manufacturers, 
the Alliance argued that it is unfair to ask vehicle manufacturers to 
certify TPMS compliance with all replacement tires of a given size. 
Finally, the Alliance contended that existing TPMSs work in an 
acceptable fashion with replacement tires in the field and that the 
agency has not provided any evidence to support an assumption to the 
contrary.
    The Alliance supplemented its petition with a letter providing data 
intended to support its position that a vehicle's TPMS should not be 
required to comply with FMVSS No. 138 with replacement tires. Among 
other things, the letter provided data on the number of tires of the 
same size for various vehicles and on characteristic differences 
between original equipment and replacement tires of the same size. More 
specifically, the Alliance presented data on the specifications for 33 
replacement tires (P195/75R14), showing differences in overall diameter 
and revolutions per mile, among other specifications. However, the 
Alliance did not explain in its petition how these differences in 
overall diameter and revolutions per mile, for each of the 33 tires, 
affected compliance for vehicles with indirect TPMSs.
    The supplementary letter also included data from a study of the 
number of replacement tires that are available for a given vehicle 
model. For 61 vehicle models, an average of 5 tire sizes are 
recommended by the manufacturer, and an average of 162 different tire 
models are available per vehicle. Data were provided to show also the 
negative effect that steel reinforcement in the sidewall of a tire can 
have on the signal transmission by direct TPMSs.
    The Alliance also asserted that NHTSA has not established a safety 
need that would justify requiring manufacturers to certify that TPMSs 
will function with replacement tires. Alternatively, the Alliance 
argued that if the agency does identify such a safety need, NHTSA 
should undertake rulemaking to standardize and tighten the performance 
requirements for replacement tires to ensure that their revolutions per 
kilometer (RPK) profiles are within the range that can work with TPMSs 
designed to meet the requirements of FMVSS No. 138.
    The Alliance also argued that there is no precedent for such a 
broad requirement, noting that manufacturers are not required to 
certify vehicle compliance with FMVSS Nos. 105 and 135 for all 
available replacement brake linings, or to certify vehicle compliance 
with crashworthiness performance requirements for all aftermarket body, 
restraint, or interior components. The Alliance and Johnson Controls 
petitions also objected to high testing costs associated with the TPMS 
requirements for replacement tires, which the Alliance estimates to be 
between $3.2 million and $106.5 million.
    Consequently, the Alliance requested that the agency revise FMVSS 
No. 138 to delete paragraph S4.4, so that vehicle manufacturers are 
only required to certify compliance with the TPMS standard with any 
tire released as original equipment on the vehicle.
    The JATMA petition took a view contrary to the other petitions 
regarding TPMS compliance with replacement tires, urging NHTSA to 
strengthen that portion of the standard so as to require the TPMS to 
function properly even with tires of a type different than the standard 
and optional tires recommended by the manufacturer. JATMA reasoned that 
failure of the TPMS to function properly with such tires could lead to 
significant confusion among consumers.
    In a letter dated September 11, 2003, General Motors (GM) submitted 
information to NHTSA intended to illustrate additional difficulties 
associated with the TPMS standard's replacement tire requirement, 
specifically problems associated with certifying run-flat tires with 
direct TPMSs.\22\ According to GM, on the basis of validation testing, 
it certified a MY 2004 vehicle equipped with run-flat tires to the 
requirements of the June 5, 2002 final rule. However, the company later 
decided to test the vehicle with a set of replacement run-flat tires. 
During testing with those replacement tires, the TPMS produced a series 
of erroneous warnings. GM stated that the root cause was an attenuated 
signal from the TPMS sensors as a result of the replacement tires' 
thicker sidewall construction. GM stated that its test further 
demonstrates that it is not practicable to require vehicle 
certification under FMVSS No. 138 for all replacement tires.
---------------------------------------------------------------------------

    \22\ Docket No. NHTSA-2000-8572-275.
---------------------------------------------------------------------------

    Since the Second Circuit's decision, NHTSA has continued to gather 
information regarding the benefits and limitations of a requirement 
that a TPMS continue functioning when any replacement tires of a size 
recommended or authorized by the vehicle manufacturer are installed on 
the vehicle. On October 20, 2003, the Alliance and several of its 
members presented additional data regarding their research into direct 
TPMS operation with replacement tires.\23\ Although by no means a 
comprehensive analysis of all replacement tires, the Alliance data 
identified 20 replacement tires with which the TPMS would reportedly 
not function properly.
---------------------------------------------------------------------------

    \23\ Docket No. NHTSA-2000-8572-277
---------------------------------------------------------------------------

    The Alliance stated that there are a small number of replacement 
tires that are problematic for direct TPMSs due to signal attenuation. 
Problems may arise from aspects of tire design and construction, such 
as high carbon content in low aspect-ratio tires, thicker sidewall, or 
steel body ply sidewall. Some tires with these characteristics may 
weaken the radio frequency signal from a direct TPMS's sensors to its 
receiver, potentially resulting in inaccurate tire inflation pressure 
information or overt failure of the system to operate. These data 
suggest that the scope of the signal attenuation problem is broader 
than just the issue of steel sidewall tires documented in earlier 
Alliance submissions.
    RMA also submitted information on the prevalence of tires with 
characteristics identified as being incompatible with proper TPMS 
functioning, at least in some cases. As noted above, these problems are 
primarily related to the tires' construction (e.g., run-flat tires) and 
material content (e.g., high carbon content in low aspect-ratio tires, 
thicker sidewall, or steel body ply sidewall). According to the RMA, in 
2002, light vehicle tires having either steel body ply cords (steel 
casing tires) or run-flat capability accounted for less than 0.5 
percent of tires distributed in the United States.\24\
---------------------------------------------------------------------------

    \24\ Letter from Steven Butcher, Vice President, Rubber 
Manufacturers Association, to NHTSA (October 31, 2003) (Docket No. 
NHTSA-2000-8572-282).
---------------------------------------------------------------------------

    In an effort to develop a test protocol to evaluate a tire's radio 
frequency signal attenuation (the most significant problem for direct 
TPMSs), the Alliance conducted an analysis of nearly 100 tires, 
including 28 of the most popular replacement tires with 14, 15, and 16-

[[Page 55904]]

inch rim sizes.\25\ The Alliance stated that its testing included both 
original equipment (OE) tires and high-volume, non-OE replacement 
tires. According to the Alliance, the proper functioning of a TPMS is 
dependent upon the interaction of the system's various components. It 
said that factors such as wheel material, wheel shape, and the mounting 
of the sensor in the wheel all can affect transmission of the TPMS 
signal.
---------------------------------------------------------------------------

    \25\ Letter from Vann Wilber, Vehicle Safety and Harmonization 
Director, Alliance of Automobile Manufacturers, to NHTSA (December 
17, 2003) (Docket No. NHTSA-2000-8572-287).
---------------------------------------------------------------------------

    The Alliance presented its findings and a proposed solution to the 
replacement tire issue in a December 9, 2003 letter to NHTSA.\26\ Based 
upon the results of its testing, the Alliance reached two basic 
conclusions. First, the Alliance stated that most replacement tires 
were found to be compatible with the TPMS tested. Second, the Alliance 
asserted that ``to date we have not been able to identify appropriate 
performance measures that would reliably identify those few replacement 
tires that are likely to undermine the proper functioning of tire 
pressure monitoring systems.''\27\ The Alliance stated that other than 
steel sidewall construction, there was no obvious construction or size 
characteristics that distinguished run-flat, low profile, and non-steel 
sidewall tires that permit proper TPMS functioning from those that 
preclude proper TPMS functioning.
---------------------------------------------------------------------------

    \26\ Letter from Vann Wilber, Vehicle Safety and Harmonization 
Director, Alliance of Automobile Manufacturers, to NHTSA (December 
9, 2003) (Docket No. NHTSA-2000-8572-285).
    \27\ Id.
---------------------------------------------------------------------------

    In its December 9, 2003 letter, the Alliance recommended that NHTSA 
consider a two-step approach that would provide information to 
consumers regarding replacement tire compatibility with TPMSs, as a 
substitute for the replacement tire certification requirement. First, 
the Alliance recommended that the vehicle owner's manual should contain 
specified language alerting consumers to select appropriate replacement 
tires that are compatible with the vehicle's TPMS. Second, the Alliance 
recommended that NHTSA should require vehicle manufacturers to provide 
an in-vehicle indication when there is inadequate signal reception from 
one or more of the TPMS sensors (either through a dedicated telltale, a 
separate function of the low tire pressure telltale, a message on a 
reconfigurable display, or some other means). In an attachment to its 
letter, the Alliance also provided draft regulatory language that would 
implement its recommended approach.
    After considering the arguments in the petitions and the 
supplemental information on TPMS compatibility with replacement tires, 
we have tentatively decided to alter our approach to this topic. 
However, we emphasize that it would not be permissible for dealers to 
install tires on a new vehicle that would take the vehicle out of 
compliance with the TPMS standard. In addition, we are proposing to 
only require vehicle manufacturers to assure TPMS compliance with the 
tires installed on the vehicle at the time of initial vehicle sale. 
However, we are proposing certain new requirements designed to address 
the issue of continuing TPMS functionality, including incorporation of 
a TPMS malfunction indicator and additional language in the owner's 
manual discussing replacement tire compatibility with the tire pressure 
monitoring system. The portions of our proposal related to replacement 
tires build upon the approach recommended by the Alliance.
    Several factors contributed to our decision to alter how we would 
address the need to have the TPMS continue functioning properly after 
the vehicle's original tires are replaced. First, information presented 
to NHTSA shows that there are currently over four million TPMS-equipped 
vehicles.\28\ Neither the agency nor vehicle manufacturers have 
received reports indicating any significant performance problems with 
those TPMSs when replacement tires are installed on the vehicle. In 
addition, the agency has noted previously that aftermarket direct TPMSs 
are available and that such systems may be capable of functioning 
regardless of the construction of the tires.\29\ NHTSA does not have 
any information to suggest a significant problem with the operation of 
aftermarket TPMSs, although the performance capabilities of these 
systems are not known. This significant real world population of TPMSs 
suggests that TPMSs will continue to work with replacement tires in the 
vast majority of cases.
---------------------------------------------------------------------------

    \28\ Letter from Robert Strassburger, Vice President, Alliance 
of Automobile Manufacturers, to NHTSA (October 20, 2003) (Docket No. 
NHTSA-2000-8572-277).
    \29\ 67 FR 38704, 38731 (June 5, 2002).
---------------------------------------------------------------------------

    However, NHTSA has been presented with data demonstrating that a 
very small number of replacement tires (estimated at less than 0.5 
percent of production) may have construction characteristics and 
material content that cause the vehicle's TPMS to exhibit functional 
problems. There is no clear design solution for this problem. In many 
instances, TPMSs may function properly even when equipped with 
replacement tires with the previously discussed characteristics. 
However, to date, it has not been possible to develop an appropriate 
performance measure that would reliably identify those anomalous tires 
that would prevent proper TPMS functioning.
    Further, it is NHTSA's understanding that some of the reported 
compatibility problems between direct TPMSs and certain replacement 
tires may have been related to vehicle manufacturer use of TPMS 
transmitters and receivers produced by different suppliers.\30\ 
Incompatibility between different parts of the TPMS may have 
contributed to the overall problem in those cases. Thus, cognizance of 
this problem may limit further the number of incidents of 
incompatibility between TPMSs and replacement tires.
---------------------------------------------------------------------------

    \30\ GM submitted a letter to NHTSA on September 11, 2003, 
outlining the problems that their direct TPMS was experiencing when 
different run-flat tires were installed on the vehicle. (Docket No. 
NHTSA-2000-8572-275) Subsequent discussions revealed that TPMS 
components from different TPMS manufacturers were used and that the 
same tires permitted proper TPMS functioning when TPMS components 
from a single TPMS manufacturer were used.
---------------------------------------------------------------------------

    Based upon the above new information, we now believe that there is 
not a sufficient basis to require vehicles to comply with FMVSS No. 138 
with all replacement tires. While the number of tires expected to be 
incompatible with the TPMS is small, such a requirement would 
nonetheless raise significant practicability concerns.
    We continue to believe, however, that the TPMS should continue to 
function properly beyond the point at which the vehicle's original 
tires are replaced, a clearly foreseeable event. Continued TPMS 
functionality with replacement tires is consistent with Congress's 
intention to improve tire and vehicle safety, as expressed in the TREAD 
Act. Moreover, there are other TPMS failure modes (e.g., pressure 
sensor battery life, pressure sensor failure, antenna failure, TPMS 
power loss), and unless drivers are made aware of such failures, they 
could have a false sense of security. Therefore, in this NPRM, we are 
proposing to require the TPMS to be equipped with a telltale indicator 
that would alert the driver of a TPMS malfunction, tire-related or 
otherwise. In addition, we are proposing owner's manual requirements to 
make consumers aware of this potential problem. The details of these 
proposed requirements immediately follow.

[[Page 55905]]

    We believe that this approach offers a reasonable alternative that 
would not only facilitate continued proper TPMS operation with 
replacement tires, but also would provide the driver with valuable 
information regarding malfunction of the TPMS.
a. TPMS Malfunction Indicator
    In proposing to require a malfunction indicator, NHTSA sees an 
opportunity not only to provide a means of warning when incompatible 
replacement tires have been installed on the vehicle, but at the same 
time also to provide the driver with notice when some other problem has 
rendered the TPMS inoperative. We are proposing to require a TPMS 
malfunction indicator that ``illuminates whenever there is a 
malfunction that affects the generation or transmission of control or 
response signals in the vehicle's tire pressure monitoring system.'' 
Examples of malfunctions that would trigger the TPMS malfunction 
indicator include, but are not limited to, the following: (1) Loss of 
power or insufficient power to the TPMS control unit; (2) loss of power 
or insufficient power from one or more wheel sensors due to a low or 
dead battery; (3) inadequate signal transmission from one or more TPMS 
sensors, or (4) inadequate signal reception by the system's antenna/
receiver, attributable to a defective wheel sensor, a defective 
antenna, or incompatible replacement tire.\31\ We believe that 
operational details of when the malfunction indicator would be 
triggered will depend upon the strengths and limitations of a given 
TPMS. We request comment on whether our proposed requirement for 
malfunction detection is sufficiently broad to detect and report TPMS 
malfunctions, regardless of the type of system installed. We also 
request comment on whether our proposed requirement is sufficiently 
specific to enable manufacturers to know the types of malfunctions the 
system must be capable of detecting and reporting. If not, we request 
comments on how it should be made more specific.
---------------------------------------------------------------------------

    \31\ We are not proposing to require the TPMS malfunction 
indicator to illuminate when a spare tire without a TPMS transmitter 
is used, because we believe that a consumer would not be lulled into 
a false sense of security under that scenario.
---------------------------------------------------------------------------

    Under the proposal, the malfunction indicator would not be required 
to specify the cause of the malfunction. We have tentatively decided 
not to establish such a requirement for several reasons. First, a 
multiplicity of TPMS malfunction messages could confuse the consumer. 
Second, there are obvious space limitations on the instrument panel or 
reconfigurable display, space that might more prudently be reserved for 
some other safety warning in the future. In addition, we believe that 
for most consumers, correction of a TPMS malfunction will necessitate 
vehicle servicing by a trained professional.
    We believe that it is important that the message for TPMS 
malfunction be distinct from the message for low tire pressure. We are 
proposing to allow manufacturers to choose from two options \32\ for 
the TPMS malfunction indicator to ensure that distinctness.
---------------------------------------------------------------------------

    \32\ We note that, under either proposed option, it would be 
permissible to incorporate the TPMS malfunction indicator as part of 
a reconfigurable display, provided all proposed requirements are 
met.
---------------------------------------------------------------------------

(1) Separate TPMS Malfunction Telltale
    Under the first proposed option, a vehicle manufacturer would be 
required to install a dedicated yellow telltale (pictured below) that 
is separate from the low tire pressure warning indicator and that would 
illuminate upon detection of a malfunction and remain continuously 
illuminated as long as the malfunction exists, whenever the ignition 
locking system is in the ``On'' (``Run'') position. It also would be 
required to perform a bulb-check at vehicle start-up. This TPMS 
malfunction telltale would be required to be labeled with the symbol 
below, or that symbol and the word ``TPMS.''
[GRAPHIC] [TIFF OMITTED] TP16SE04.008


[[Page 55906]]


    We are proposing yellow (as opposed to red) as the appropriate 
color for the dedicated malfunction telltale because, in most cases, 
malfunction of the TPMS would not constitute an imminent safety problem 
necessitating immediate driver action. A vehicle's tires may be 
properly inflated, even if the malfunction indicator is triggered. 
Therefore, we believe that a yellow cautionary telltale would be 
appropriate to indicate that while a problem with the TPMS exists, the 
vehicle may be driven safely until the opportunity arises to have the 
situation corrected.
    We are proposing that, once triggered, this separate TPMS 
malfunction indicator would be continuously illuminated as long as the 
malfunction exists, whenever the ignition locking system is in the 
``On'' (``Run'') position. We are making this proposal because the TPMS 
is an important piece of safety equipment, and we believe that the 
driver should be constantly reminded when such equipment is not 
operating properly. The requirement for constant illumination is 
consistent with the operation of other warning telltales.
    After conducting an evaluation of possible icons, NHTSA selected 
the proposed symbol for TPMS malfunction, which is based upon an 
international ISO design used to signal low tire pressure. In selecting 
the proposed symbol, we sought to choose an icon that could be 
recognized by consumers, that would help achieve the desired response, 
and that at the same time would be consistent with the ISO standard. If 
the consumer were not already familiar with the telltale, the preferred 
response would be to lead people to consult the owner's manual for 
further information, rather than an extreme response (e.g., stopping 
the vehicle immediately).
    As in the case of the requirement for bulb checks for other 
telltales, we believe that the proposed requirement for a bulb check 
for the malfunction telltale would provide an important safety benefit 
(i.e., ensuring that the telltale is capable of illuminating in order 
to deliver its message) at minimal cost.
    (2) Combination Low Tire Pressure/TPMS Malfunction Telltale
    Under the second proposed option, a vehicle manufacturer could 
incorporate the TPMS malfunction indicator function as part of the 
required low tire pressure telltale. Proposed requirements for color, 
wording, bulb check, and illumination format for the low tire pressure 
function (all discussed elsewhere in this proposal), would be 
unaffected by the incorporation of the TPMS malfunction indicator 
within the same telltale.
    In order to indicate a malfunction, the low tire pressure telltale 
would be required to flash for a period of one minute, after which time 
the telltale would remain continuously illuminated as long as the 
malfunction exists and the ignition locking system is in the ``On'' 
(``Run'') position. We limited the period to one minute to avoid 
distracting or bothering the driver. This flashing and illumination 
sequence would be repeated upon subsequent vehicle start-ups until the 
situation causing the malfunction has been corrected. We believe that 
flashing the low tire pressure telltale to indicate TPMS malfunction is 
a sufficiently distinct message to enable the driver to differentiate 
between the two warnings; any confusion between the messages would be 
resolved easily by consulting the owner's manual.
    The agency is especially interested in comments related to the 
specific details of the mode of operation of the proposed TPMS 
malfunction indicators, as well as possible alternatives. We invite 
views on the telltales' malfunction symbol(s) and how the signal is 
presented to the driver, in order to assess its effectiveness in 
delivering a clear message.
b. Owner's Manual Requirements Related to Replacement Tires and the 
TPMS Malfunction Indicator
    The second part of our proposed approach for addressing continued 
operation of the TPMS with replacement tires involves requiring vehicle 
manufacturers to provide relevant information to consumers in the 
vehicle owner's manual. Generally, we are proposing to require language 
to alert consumers regarding: (1) Potential problems related to 
compatibility between the vehicle's TPMS and various types of 
replacement tires, and (2) the presence and operation of the TPMS 
malfunction indicator. For those vehicles without an owner's manual, we 
are proposing to require that this information be supplied to the 
purchaser in writing at the time of initial vehicle sale. We request 
comments on our proposed owner's manual language, including any 
suggestions for modifications and accompanying rationale.
    Specifically, under paragraph S4.5 of the standard, we are 
proposing to require the following language to be printed in the 
vehicle's owner's manual:

    Your vehicle has also been equipped with a TPMS malfunction 
telltale to indicate when the system is not operating properly. When 
the malfunction telltale is illuminated, the system may not be able 
to detect or signal low tire pressure as intended. TPMS malfunctions 
may occur for a variety of reasons, including the installation of 
incompatible replacement tires on the vehicle. Always check the TPMS 
malfunction telltale after replacing one or more tires on your 
vehicle to ensure that the replacement tires are compatible with the 
TPMS.

2. Spare Tires
    In the June 5, 2002 final rule, we decided not to require the TPMS 
to monitor the pressure in a spare tire (either compact or full-sized), 
either while stowed or when installed on the vehicle (67 FR 38704, 
38731). We came to this decision for a number of reasons, including the 
knowledge on the part of drivers that temporary tires are not intended 
for extended use, the fact that compact spare tires pose operational 
problems for both direct and indirect TPMSs, the potential disincentive 
for manufacturers to supply a full-size spare if TPMS compliance were 
required, and the increased cost of the rule, with little if any safety 
benefit, if a spare tire must be monitored. NHTSA stated that it would 
not conduct compliance testing under Standard No. 138 with spare tires 
installed on the vehicle.
    The Alliance petition asked NHTSA to further clarify the final rule 
to acknowledge that a properly calibrated TPMS will activate the TPMS 
telltale after a small spare tire or a full-sized spare tire without a 
pressure sensor is installed. According to the Alliance, in situations 
in which a spare tire is in use, information regarding the inflation 
pressure of the remaining three tires may or may not be indicated by 
the TPMS, depending upon the type of system and display used. The 
Alliance asked for an explicit statement that the standard does not 
require a TPMS to indicate low pressure in any of the remaining three 
tires when a spare tire is installed on a vehicle.
    We acknowledge that in certain instances, use of a spare tire on a 
vehicle may prevent the proper operation of the TPMS. However, we 
believe that the Alliance's recommended regulatory language is 
unnecessary, because the proposed language in paragraph S4.5, Written 
Instructions, of the NPRM adequately addresses this issue. That 
provision proposes to permit a vehicle manufacturer to include in the 
vehicle owner's manual a statement of ``whether the tire pressure 
monitoring system functions with the vehicle's spare tire (if 
provided).'' This proposed language is sufficient to cover all aspects 
of a

[[Page 55907]]

TPMS's capability to function when a spare tire is in use.
    In addition, during the course of this rulemaking, GM suggested a 
clarification in paragraph S4.5.1 of the standard, which deals with 
TPMS-related written instructions in the vehicle owner's manual (see 
Docket No. NHTSA-2000-8572-258 in the DOT Docket Management System Web 
site at http://dms.dot.gov). Specifically, GM noted that vehicle 
manufacturers are not required to provide a spare tire, and some 
vehicles do not come equipped with spare tires. Consequently, GM 
suggested that the standard be amended to reflect this possibility, 
thereby preventing consumer confusion.
    We agree with GM that not all vehicles are equipped with spare 
tires and that consumers might be confused to see language in the 
owner's manual, as contained in the June 2002 final rule, for a vehicle 
that is not equipped with a spare tire. Accordingly, in the NPRM, we 
have drafted proposed paragraph S4.5 to reflect the potential absence 
of a spare tire.\33\
---------------------------------------------------------------------------

    \33\ NHTSA has eliminated the owner's manual requirement 
contained in S4.5.2, due to the Second Circuit's invalidation of the 
underlying one-tire, 30-percent option. Accordingly, as part of this 
proposal, we have consolidated the remaining owner's manual 
requirements under S4.5 and included the change related to spare 
tires in that section.
---------------------------------------------------------------------------

3. Low Tire Pressure Telltale
    Paragraph S4.3 of FMVSS No. 138 required that each vehicle be 
equipped with a yellow telltale that is mounted in plain view of the 
driver and is identified by the symbols and phrases specified for low 
tire pressure in S5.2.3 and Table 2 of FMVSS No. 101, Controls and 
Displays.\34\ It also stated the conditions under which the TPMS 
telltale must illuminate and the conditions under which the TPMS must 
extinguish or deactivate the telltale.
---------------------------------------------------------------------------

    \34\ We note that if a vehicle manufacturer elects to install a 
low tire pressure telltale that indicates which tire is under-
inflated, the telltale must correctly identify the under-inflated 
tire. See S4.3.2.
---------------------------------------------------------------------------

    Specifically, the TPMS telltale was required to be illuminated 
continuously when low tire pressure is detected under the parameters 
set forth in S4.2 of FMVSS No. 138. In addition, it was required to be 
illuminated as a bulb check when the ignition locking system is in the 
``on'' position and the engine is not operating, or when the ignition 
locking system is in a position between ``on'' and ``start'' that is 
designated by the manufacturer as a check position. Paragraph S6(j) of 
the standard provided a test procedure, in which the TPMS telltale is 
to be extinguished automatically, although it does not specify a time 
limit for the telltale to be turned off.
    A number of the petitioners raised issues about the TPMS warning 
telltale requirements, including issues related to permissible color, 
use of reconfigurable displays, extinguishment time, bulb check, and 
indication of TPMS malfunction. A discrepancy also was identified 
between FMVSS No. 138 S4.3.1(b) and FMVSS No. 101 S5.2.3 and Table 2. 
Each of these issues will be discussed in turn. (Please note that all 
relevant telltale issues related to the newly proposed TPMS malfunction 
indicator are discussed above in Section III.C.1 (Replacement Tires).)
Color
    Petitions submitted by Volkswagen, the Alliance, and BNA's ISO/TC22 
all raised issues related to TPMS telltale color. The petition of BNA's 
ISO/TC22 recommended replacement of the yellow TPMS telltale required 
under the June 5, 2002 final rule with a red lamp, arguing that 
illumination of the TPMS telltale should be treated as an alert to the 
driver to check the tire pressure and to take corrective action 
immediately. The petitioner reasoned that the TPMS should have a red 
telltale, consistent with other failure telltales, rather than a yellow 
``warning'' telltale, which does not connote a need for immediate 
corrective action. It was mentioned that ISO, an international 
standard-setting body, is currently preparing a new standard for ``Tyre 
Pressure Monitoring Systems,'' which can be expected to have a 
requirement for a red telltale.\35\
---------------------------------------------------------------------------

    \35\ NHTSA understands that ISO had made plans to convene a 
meeting in April 2004, in order to obtain agreement on performance 
specifications and test procedures for a ``Tyre Pressure Monitoring 
Systems'' standard, with the intention of presenting a draft 
document to its members for balloting in June 2004. A date for 
issuance of a final ISO standard has not been set.
---------------------------------------------------------------------------

    Volkswagen's petition also asked the agency to modify its 
requirement in FMVSS No. 101 for the color of the TPMS telltale. 
However, Volkswagen seeks to have the standard permit a dual-color TPMS 
telltale, which would switch from yellow to red when tire pressure 
falls below a specified level deemed to be dangerously low. The 
petitioner acknowledged the possibility that such TPMS telltales may 
display as red immediately if air loss is sufficiently rapid or is 
below a safe driving level upon start-up. However, Volkswagen believes 
that a TPMS telltale with dual yellow/red illumination capabilities 
would provide an enhanced level of warning to drivers in urgent 
situations and notes that such TPMS telltales are currently in use on 
some vehicles.
    Volkswagen also asked that the final rule be modified to permit the 
use of a white lamp in the event the TPMS telltale is permitted to be 
part of a reconfigurable (multi-function) display. In line with its 
recommendations, Volkswagen's petition asked the agency to require 
vehicle owner's manuals to explain the functional meaning of the colors 
utilized for the TPMS telltale.
    The Alliance believes that the final rule's specified requirements 
for telltale color are unnecessarily design-restrictive. Its petition 
also recommended amendment of the standard to permit both the yellow/
red TPMS telltale color combination and the white TPMS telltale for 
reconfigurable displays.
    We continue to believe that yellow is the most appropriate color 
for the low tire pressure telltale, consistent with the reasoning set 
forth in the final rule, so in this NPRM, we are again proposing a 
yellow telltale requirement as part of the standard. We will briefly 
restate our reasoning. The use of the color red usually is reserved for 
telltales warning of an imminent safety hazard. An example is the brake 
system warning telltale, which is red because a failure in a vehicle's 
brake system results in an imminent safety hazard that requires 
immediate attention. In contrast, NHTSA requires a yellow telltale for 
driver warnings when the safety consequences of the malfunctioning 
system do not constitute an emergency and the vehicle does not require 
immediate servicing.
    Tire pressure monitoring systems are designed to detect a 
relatively slow loss of tire pressure so that the driver can seek the 
necessary tire maintenance and prevent a major tire failure that could 
result in catastrophic consequences (i.e., the type of situation where 
a red telltale would be suitable). Based upon the agency's testing of 
tires at 20 pounds per square inch (psi) (the minimum activation 
pressure for the TPMS telltale), we do not believe that a significantly 
under-inflated tire represents an imminent safety hazard, particularly 
because we are proposing a requirement for under-inflation detection 
and warning at a point when the vehicle may still be operated safely.
    If we were to require a red telltale, we would be conveying a very 
different message regarding the urgency of the low tire pressure 
situation and the action to be taken (i.e., the need for an immediate 
stop). If we were to permit a telltale that changes color from yellow 
to red, we are concerned that this could confuse consumers, 
particularly if it is left to the discretion of individual vehicle 
manufacturers to decide the

[[Page 55908]]

level of under-inflation at which the red telltale is triggered. 
Conceivably, a manufacturer could program the TPMS to illuminate a 
yellow telltale for a fraction of a second, after which time it would 
immediately turn red; such a result would meet the letter of the 
requirement, but foil its intent. Accordingly, we stand by our 
conclusion that yellow is the appropriate color for the low tire 
pressure telltale because it conveys the message that the driver may 
continue driving, but should check and adjust the tire pressure at the 
earliest opportunity.
    Although we are proposing to retain the yellow color requirement 
for the low tire pressure telltale in this NPRM, it has traditionally 
been our practice to permit manufacturers to take additional measures, 
consistent with Federal motor vehicle safety standards, that are 
designed to further enhance safety. Consequently, we are proposing to 
permit manufacturers to incorporate a second, red light to accompany 
the continuously-illuminated yellow TPMS telltale, which would be 
illuminated when pressure in one or more tires becomes dangerously 
under-inflated, as determined by the manufacturer. If a manufacturer 
chooses to add a second, red warning light, its meaning and function 
would have to be discussed in the vehicle's owner's manual.
    NHTSA has not adopted the recommendation that the agency waive the 
yellow color requirement to also permit a white color for TPMS 
telltales that are part of a reconfigurable display. We believe that 
color imparts meaning in the context of warning telltales, and the 
petitioners have provided insufficient data to justify exempting TPMS 
telltales in reconfigurable displays from being subject to the 
standard's proposed yellow color requirement.
Reconfigurable Display
    The petitions for reconsideration submitted by Johnson Controls, 
Volkswagen, and the Alliance all raised concerns related to the 
permissibility of incorporating the TPMS telltale in reconfigurable, 
multi-function displays. Reconfigurable displays utilize a common space 
to provide a variety of information to the driver; typically, these 
displays have a screen on which different messages may occupy the same 
position at different times.
    While acknowledging the agency's concerns regarding the safety 
implications of permitting a vehicle operator to deactivate the TPMS 
telltale or reconfigure the display so that the TPMS telltale is not 
visible, the Johnson Controls petition stated that reconfigurable 
displays can be designed to meet the requirements of the June 5, 2002 
final rule. Specifically, a reconfigurable telltale could be produced 
that automatically illuminates and remains continuously illuminated 
while one or more tires are significantly under-inflated and that is 
extinguished only when the tires cease to be significantly under-
inflated. (We assume that other messages that normally share the same 
position on the reconfigurable display as the TPMS telltale either 
would be suppressed or migrate to a different position on the display.) 
Johnson Controls asked the agency to clarify the TPMS rule to 
acknowledge that the TPMS telltale may be part of a reconfigurable 
display, provided that the above two conditions are met. The petitioner 
noted that this clarification would not require any substantive change 
to the TPMS standard, but it would allow manufacturers to continue to 
have the option of utilizing multi-function display technology while 
fully complying with the requirements of the regulation.
    Volkswagen's petition argued that the final rule's telltale 
requirements are too design restrictive and requested that the TPMS 
telltale be permitted as part of a reconfigurable display that 
illuminates the TPMS telltale when the vehicle is shifted into a 
forward driving gear and which displays the telltale on an 
interruptible but persistent basis until the tire pressure is corrected 
or until the system is reset manually in accordance with the vehicle 
manufacturer's instructions.
    In the interest of safety, we incorporated a requirement in the 
June 5, 2002 final rule for continuous illumination of the TPMS 
telltale as long as one or more of a vehicle's tires is significantly 
under-inflated. While the TPMS rule did not explicitly prohibit the 
incorporation of the TPMS telltale into a reconfigurable display, we 
questioned the ability of a reconfigurable display to meet the 
requirements of S4.2 of the standard, due to the constant illumination 
requirement. In drafting the June 2002 final rule, we were concerned 
also that a vehicle operator may be able to reconfigure the display in 
such a way that the important safety message provided by the TPMS 
telltale is no longer visible, which is not acceptable.
    In the current proposal, FMVSS No. 138 once again would not 
prohibit outright the inclusion of the TPMS telltale as part of a 
reconfigurable display, and we note Johnson Controls' statement that 
reconfigurable displays currently exist which can meet the proposed 
requirements of the standard, including the provision for continuous 
illumination. Thus, we want to make it clear that we are proposing that 
it would be permissible to incorporate the TPMS telltale as part of a 
reconfigurable display, provided that illumination of the yellow 
telltale is continuous while one or more tires is under-inflated. 
However, we want to emphasize that under this proposal, the TPMS 
telltale would not be permitted to flash or cycle when performing its 
under-inflation detection function. Further, the display could not be 
controlled by the driver so as to disable the TPMS safety message prior 
to remedying the low pressure condition, including by scrolling the 
message down such that it is no longer visible. Thus, reconfigurable 
displays that provide a persistent, but cycling, TPMS warning would not 
meet the standard's proposed requirement for continuous illumination.
Extinguishment Time
    The Johnson Controls petition asked the agency to amend the June 
2002 final rule to specify a timing requirement for TPMS telltale 
extinguishment, in cases in which the tire pressure deficiency has been 
corrected and there is no manual reset feature. In recommending a 
timeframe for extinguishment, the petitioner stated that because both 
illumination and extinguishment of the telltale involve the same 
detection considerations from a technological standpoint, 
extinguishment should occur within ten minutes. Accordingly, Johnson 
Controls petitioned NHTSA to amend the testing procedures in FMVSS No. 
138 S6(j) of the June 5, 2002 final rule to provide that unless there 
is a manual reset feature, the manufacturer must record the time to 
extinguishment after the vehicle reaches 50 km/hr and that the TPMS 
telltale must extinguish within ten minutes. The petitioner also asked 
that the testing procedures in FMVSS No. 138 S6(i) be amended to 
require verification of telltale extinguishment if the TPMS system has 
a manual reset feature.
    We are not adopting the suggestion of Johnson Controls to require a 
time limit for TPMS telltale extinguishment. Telltale extinguishment is 
addressed already under FMVSS No. 101. Specifically, paragraph S5.3.1 
of FMVSS No. 101 provides, ``A telltale shall not emit light except 
when identifying the malfunction or vehicle condition for whose 
indication it is designed or during a bulb check upon vehicle 
starting.'' The TPMS telltale is not excluded from this requirement.
    NHTSA has not imposed specific time limits for extinguishment of 
other telltales, and given the existing

[[Page 55909]]

requirements of FMVSS No. 101, we do not believe it is necessary to do 
so for the TPMS telltale at this time, although we acknowledge that 
TPMS technology may require a certain period of time to detect that the 
low-pressure situation has been corrected before extinguishing the 
telltale.

Bulb Check

    Paragraph S4.3.3 of the June 5, 2002 final rule provided that the 
TPMS warning telltale must be activated as a check of lamp function 
either when the ignition locking system is turned to the ``On'' 
(``Run'') position when the engine is not running, or when the ignition 
locking system is in a position between ``On'' (``Run'') and ``Start'' 
that is designated by the manufacturer as a check position. However, 
the telltale need not be activated when a starter interlock is in 
operation.
    The petitions of both Volkswagen and the Alliance recommended 
changes to the June 2002 final rule's requirements related to a bulb 
check for the TPMS telltale. Volkswagen expressed agreement with the 
Alliance's recommendation in its comments on the earlier NPRM that a 
bulb check function should not be required because manufacturers 
routinely include serviceability provisions as a normal design 
practice, thereby rendering that regulatory provision unnecessary. 
Volkswagen also stated that if the TPMS telltale were permitted as part 
of a multi-functional display, the telltale would not necessarily 
illuminate because internal vehicle diagnostics monitor the system, and 
illumination of the display itself constitutes the bulb check function. 
Consequently, Volkswagen asked NHTSA to eliminate the requirement for 
the bulb check function. Alternatively, Volkswagen asked the agency to 
amend S4.3.3(a) to clarify that the bulb check function does not apply 
if the TPMS telltale is part of a reconfigurable display.
    We are proposing to retain a requirement for a bulb check for the 
TPMS low tire pressure telltale as part of this NPRM, because a bulb 
check helps ensure the functionality of the TPMS warning system in a 
consistent and uniform fashion. The safety benefits associated with the 
TPMS will only be realized if the TPMS telltale can illuminate so as to 
provide the requisite warning to the vehicle operator. Consequently, 
NHTSA continues to believe that a bulb check will provide vehicle 
operators with useful information (i.e., that the warning telltale bulb 
is functional), and these benefits will come at little, if any, 
additional cost. (This same reasoning applies to the bulb check for the 
proposed dedicated TPMS malfunction telltale, if the vehicle is so 
equipped.)
    For the safety-related reasons discussed above, we believe that the 
proposed bulb check requirement also should apply when the TPMS 
telltale is part of a reconfigurable display. However, we are proposing 
that illumination of the reconfigurable display itself would constitute 
a sufficient bulb check under the standard, as long as the low tire 
pressure telltale is one of the displays activated.
Harmonization of FMVSS 138 S4.3.1(b) and FMVSS 101 Table 2
    The petitions of Johnson Controls and the Alliance asked NHTSA to 
resolve an apparent discrepancy under the June 5, 2002 final rule 
between S4.3.1(b) of FMVSS No. 138 and S5.2.3 and Table 2 of FMVSS No. 
101. These provisions discussed the permissible use of words and 
symbols as part of the TPMS telltale. As the petitioners point out, 
FMVSS No. 101 S5.2.3 stated that for a TPMS telltale that does not 
identify which tire has low pressure, the TPMS telltale may include the 
symbol in Table 2 or the symbol and the words ``Low Tire.'' That same 
provision provided that for a TPMS telltale that does indicate which of 
the four tires is experiencing low pressure, the telltale may either 
use the symbol or the words indicated in Table 2. However, FMVSS No. 
138 S4.3.1(b) stated that the TPMS telltale must be identified by one 
of the symbols shown for the low tire pressure telltale in Table 2 of 
Standard No. 101. Consequently, the petitioners contended that these 
two provisions are unclear as to the content requirements for the TPMS 
telltale for systems that identify which tire has low pressure.
    The two petitions, however, recommended different remedies. Johnson 
Controls recommended resolving the discrepancy by modifying FMVSS No. 
138 S4.3.1(b) so as to remove the language ``one of the symbols shown 
for the 'Low Tire Pressure Telltale' in Table 2'' and replace that 
phrase with ``a telltale permitted by Section 5.2.3.'' The Alliance 
recommended modifying FMVSS No. 101 S5.2.3 so as to eliminate the two 
parenthetical phrases stating ``(that does not identify which tire has 
low pressure).'' Elimination of that phrase would have the effect of 
requiring either a symbol from Table 2 or both a symbol and words from 
Table 2.
    We agree with the petitioners that the identified provisions in 
FMVSS No. 101 and FMVSS No. 138 must be reconciled in order to denote 
clearly what constitutes a permissible TPMS telltale and thus have 
addressed this issue in the NPRM. The preamble to the June 2002 final 
rule made clear the agency's intent regarding the visual content of the 
TPMS telltale for those systems that identify which tire has low 
pressure. Specifically, the preamble stated, ``Thus, the final rule 
requires the use of this image, with lamps at the image's tires to 
indicate which tire is significantly under-inflated, if a vehicle 
manufacturer provides a display that identifies which tire is 
significantly under-inflated.'' 67 FR 38704, 38732. Without the symbol, 
the words ``Low Tire'' would not indicate which of the vehicle's four 
tires had low pressure.
    In order to resolve the discrepancy, as part of this NPRM, we are 
proposing to adopt the recommended solution put forth by the Alliance 
and rejecting the solution suggested by Johnson Controls. The 
recommended solution in the Johnson Controls petition would permit a 
manufacturer to choose a telltale displaying the words ``Low Tire'' 
without a symbol. Not only would such an outcome be at odds with the 
agency's clear intent articulated in the June 2002 final rule's 
preamble, but it would also be an inappropriate result for a TPMS 
designed to ``identify which tire has low pressure.'' Accordingly, as 
part of this NPRM, we are proposing that FMVSS No. 101 S5.2.3 require a 
TPMS symbol in all cases, with optional supplementation by the words 
``Low Tire.''
Indication of TPMS Malfunction
    The Alliance petition requested that NHTSA modify the June 2002 
final rule specifically to allow the TPMS telltale to alert the vehicle 
operator in the event of a TPMS system malfunction. The Alliance argued 
that the agency has permitted other required telltales to flash to 
indicate malfunctioning systems, but it also noted that the preamble 
and the regulatory text of FMVSS No. 138 S4.2.1 and S4.2.2 required 
constant illumination once the telltale is triggered until the low-
pressure situation is resolved. To indicate TPMS system malfunction, 
the Alliance recommended permitting the telltale to flash, as distinct 
from a steady activation pattern indicating low tire pressure, and it 
asked the agency to amend paragraphs S4.2, S4.3, and S4.5 of FMVSS No. 
138 accordingly.
    Consistent with our proposed resolution of the replacement tire 
issue, NHTSA is proposing to require the TPMS to include a TPMS 
malfunction indicator. Details of the proposed requirements for the 
TPMS malfunction

[[Page 55910]]

indicator and related matters are fully discussed under Section III.C.1 
(Replacement Tires) above.
4. Test Procedures
    A number of petitions raised issues about testing procedures under 
the June 2002 final TPMS rule, including petitions submitted by Delphi, 
DENSO, Volkswagen, and the Alliance. Concerns were raised regarding 
what petitioners perceived to be inadequate specificity and objectivity 
of those test procedures. Specifically, petitioners raised issues 
related to rim position, calibration, test specificity, and reset, each 
of which will be addressed in further detail below. In addition, 
DENSO's petition asked the agency to issue a TPMS Compliance Test 
Procedure on an expedited basis, because DENSO stated that 
manufacturers will need sufficient lead time (e.g., DENSO estimated one 
year) to implement the TPMS design specifications and to begin 
installation of TPMSs in new vehicles.
    Petitioners argued that in light of the capabilities of TPMS 
systems, specific test procedures are necessary. While we do not agree 
with all of the petitioners' contentions, in order to ensure 
objectivity, we are proposing to identify a specific test course and to 
incorporate it in the standard as part of this NPRM. This proposed 
course is the Southern Loop of the Treadwear Course, as defined in 
Appendix A and Figure 2 of 49 CFR 575.104, which is located on various 
highways in and around San Angelo, Texas. We propose that testing would 
be conducted starting at any point on the course.
    We see several benefits to this approach, foremost of which is that 
this test course could be incorporated into the standard in a timely 
fashion. It would not be necessary to design or build a new test track 
for compliance testing purposes or to conduct extensive research to 
describe such a test course.
    Further, the proposed course is well known and has been used for 
decades by NHTSA and the tire industry for uniform tire quality grading 
(UTQG) testing. Testing on a section of public highway would help to 
ensure that any required TPMS calibration will be performed 
appropriately and that low tire pressure detection would be evaluated 
appropriately during testing. Also, vehicle manufacturers would be able 
to review the course and to use it to verify compliance of their TPMS 
prior to vehicle certification. Thus, by proposing to require vehicles 
to satisfy the TPMS requirement when tested at any portion of this 
course, TPMSs would be designed to operate properly on a variety of 
roadways and conditions, and the standard would satisfy the requirement 
of objectivity.
    Designation of a specific test course in and around San Angelo 
could pose some potential problems if that section of highway were to 
experience closures related to major road repairs or damage due to 
extreme weather conditions or natural disasters. However, we believe 
that the probability of such occurrences is very small, particularly to 
the extent that the entire test course would be unavailable. Because 
the proposed test course is approximately 140 miles in length, if one 
portion were to become unavailable, testing could be conducted on a 
different segment of the course. Again, we note that this particular 
test course has been used successfully for UTQG testing purposes for a 
number of years, and we believe that it would be suitable for TPMS 
testing as well.
    Additional details are provided below regarding proposed changes to 
the standard's test conditions and procedures that reflect differences 
between the June 5, 2002 final rule and this NPRM.
Rim Position
    Under the June 5, 2002 final rule, paragraph S6(l) of the standard 
stated that the original rims are to be used with any replacement tires 
recommended by the manufacturer (that are of a suitable size to fit the 
OE rims; otherwise, appropriately sized OE rims will be used).
    The petition for reconsideration filed by Johnson Controls asked 
the agency to revise the test procedures in paragraph S6(l) to specify 
that the original rim position (i.e., left front, left rear, right 
front, right rear) will be preserved when replacement tires are placed 
on the vehicle. According to the petition, such positioning is 
important to preserve the integrity of the original training of the 
TPMS. Johnson Controls stated that most direct TPMSs require that the 
system initially be trained to recognize the transmitters on the rims 
and their relative positions on the vehicle, with such training 
routinely occurring during vehicle assembly. This change was 
recommended to prevent compliance testing in a manner that would foil 
the proper functioning of the TPMS.
    We anticipate that there will be many instances in which consumers 
and vehicle repair/service technicians will not maintain original rim 
position, either intentionally or unintentionally. As a primary 
example, many vehicle manufacturers direct owners to rotate their tires 
on a regular basis, based on time, mileage, or both. Maintaining 
original rim position during tire rotation would necessitate the 
additional time and expense of removing each tire from its wheel rim 
prior to rotation, rather than simply shifting the entire wheel and 
tire assembly, which is the normal way tires are rotated. Moreover, 
contrary to the implication of the Johnson Controls petition, some 
manufacturers of vehicles with a direct TPMS provide instructions in 
the owner's manual regarding how to reprogram the TPMS sensors 
following wheel rotation (see, e.g., the TPM sensor identification 
codes section of the MY 2004 GMC Yukon owner's manual, at page 5-74).
    However, after considering the Johnson Controls petition, we have 
drafted a new paragraph S5.3.3, Rim position, in the NPRM to provide 
that we would maintain the original rim positions when conducting 
compliance testing in those cases in which the vehicle manufacturer 
directs owners to retain the original rim positions in the owner's 
manual. We would also follow any instructions contained in the vehicle 
owner's manual related to tire rotation and rim position, regardless of 
whether such instructions are included in a discussion of the TPMS or 
in some other portion of the owner's manual. If a vehicle manufacturer 
does not make such rim position recommendations, the agency would be 
free to mount the rims in any position on the vehicle when conducting 
compliance testing. (If the tires and rims on the front and rear axles 
were not the same size, the tires and rims would remain on the 
appropriate axle. We would ensure also that unidirectional tires are 
mounted appropriately.\36\) Before conducting such compliance tests, 
the agency would follow all manufacturer recommendations with respect 
to reprogramming the TPMS to account for changes in rim positions.
---------------------------------------------------------------------------

    \36\ Unidirectional tires are tires that are designed to rotate 
in one specified direction during forward motion. This directional 
limitation is primariliy based upon tread pattern design.
---------------------------------------------------------------------------

Calibration
    As part of the June 2002 final rule's test procedures, paragraph 
S6(d) specified that the vehicle be driven at any speed between 50 km/
hr and 100 km/hr for 20 minutes prior to conducting the TPMS low 
inflation pressure detection test. This procedure was designed to 
calibrate or to establish a baseline for the TPMS. As noted in the June 
5, 2002 final rule, indirect TPMSs need time to calibrate the system 
under certain circumstances, such as when a vehicle is driven for the 
first time (i.e., when it is new), when pressure in a tire is changed, 
and when the tires are replaced or rotated. 67 FR 38704, 38730.

[[Page 55911]]

Until the system is properly calibrated, the TPMS may not be available 
to monitor the vehicle's tire inflation pressure fully.
    The petitions submitted by both Volkswagen and the Alliance raised 
issues involving TPMS calibration and related test procedures. The two 
petitioners argued that the test procedures in paragraph S6(d) do not 
include sufficient detail and are design restrictive.
    Volkswagen's petition sought clarification that TPMS calibration is 
necessary when any one of the above-discussed three conditions occurs. 
We acknowledge that calibration (or recalibration) of an indirect TPMS 
may be necessary when any one of the above-stated conditions occurs. 
Beyond this statement of clarification, we have also drafted this NPRM 
so as to further accommodate the need for TPMS calibration, as 
discussed below. These proposed changes include designation of a 
specific test course and the inclusion of an expanded test procedure 
for the ``system calibration/learning phase'' (S6(d)). We believe that 
these measures would address the issues raised by the petitioner 
regarding calibration.
    Volkswagen's petition also asked the agency to modify the test 
procedures in paragraph S6(d), which are designed to provide sufficient 
initial driving time for indirect TPMSs to properly calibrate. Again, 
that provision specified that the vehicle be driven for 20 minutes at 
any speed specified in paragraph S5.3.2 (i.e., between 50 km/h (31.1 
mph) and 100 km/h (62.2 mph)). However, Volkswagen argued that 
paragraph S6(d) is not sufficiently specific to simulate the reasonable 
and common driving conditions necessary for calibration of the TPMS. 
Volkswagen asserted that for proper calibration of the TPMS, the 
vehicle must be driven at least a minimal amount of time in various 
speed ranges and within limits of forward and lateral acceleration. 
According to Volkswagen, driving for calibration purposes should be on 
reasonably straight roads, at controlled and reasonable speeds in the 
turns, and with limited and moderated acceleration and braking.
    Consequently, Volkswagen asked NHTSA to amend S6(d) to include a 
statement that the vehicle shall be driven in accordance with the 
manufacturer's specification. The Volkswagen petition stated that this 
change would be consistent with the procedure in other standards in 
which the vehicle manufacturer specifies test parameters, such as those 
for fuel tank capacity, seat back angle and vehicle seat track 
position, and vehicle weight.
    The Alliance petition also supported greater specificity in the 
TPMS test procedures, including paragraph S6(d). The petitioner argued 
that those test procedures are overly design-restrictive and may hamper 
development and performance of indirect TPMSs. The Alliance provided a 
detailed discussion of the various TPMS algorithms and the 
corresponding relationship between the complexity, capabilities, and 
timing requirements of such algorithms. The Alliance asked the agency 
to substitute a calibration procedure specified by the manufacturer in 
the specified range of test speeds from 50 to 100 km/hr.
    Although the Second Circuit's decision likely will lead to 
increased use of direct TPMSs in the near term, NHTSA has decided to 
address the calibration issue in any event, in anticipation of the use 
of indirect TPMSs (or other systems for which calibration issues may be 
important) that can meet the requirements of the standard. Because 
NHTSA strives for standards that are technology-neutral, issues raised 
in the petitions for reconsideration related to test procedures, 
including but not limited to calibration, remain ripe for resolution.
    While NHTSA acknowledges that the performance of an indirect TPMS 
may be sensitive to road conditions and vehicle operating conditions, 
it is important to ensure that each TPMS performs its intended function 
during normal driving by the public. The purpose of paragraph S6(d) of 
the TPMS test procedure, under both the June 5, 2002 final rule and 
this NPRM, is to provide an opportunity for the vehicle to learn the 
variables associated with distinct tire types under varying conditions. 
Thus, we reject the suggestion that NHTSA be required to conduct its 
compliance testing in accordance with the manufacturer's 
specifications. That would allow a manufacturer to design a TPMS that 
would function only in very limited circumstances, as opposed to the 
wide variety of circumstances found in real-world driving.
    We also believe that it is necessary to specify some objective 
limit on calibration time for the following reasons. First, if the 
calibration period is excessively long (e.g., several hours), there is 
an increased chance that the vehicle could develop a serious leak 
leading to significant tire under-inflation for which the TPMS would 
provide no warning. Second, the public is likely to expect that, after 
they follow the reset instructions in the vehicle owner's manual, the 
TPMS will function as intended within a brief period of time. Further, 
TPMS manufacturers have stated that their systems can properly 
calibrate within 20 minutes, which demonstrates that such a timeframe 
is practicable.\37\
---------------------------------------------------------------------------

    \37\ See e.g., Docket No. NHTSA-2000-8572-259.
---------------------------------------------------------------------------

    In order to ensure that our test procedures for calibration reflect 
normal driving situations and to ensure objectivity, in the NPRM, we 
are proposing to change paragraphs S5 and S6 as follows:
    (1) We are proposing that the road test surface for compliance 
testing, including calibration, would be any portion of the Southern 
Loop of the Treadwear Course defined in Appendix A and Figure 2 of 49 
CFR 575.104. (See S5.2);
    (2) We are proposing a new paragraph entitled System calibration/
learning phase which would specify that the vehicle be driven in one 
direction for 10-15 minutes cumulatively (not necessarily continuously) 
within a speed range of 50-100 km/h, and then driven for 5-15 minutes 
under similar conditions in the opposite direction. The sum of the 
total cumulative driving time in both directions would not be less than 
20 minutes. Time would not accumulate during periods when the brake 
pedal is applied. (See S6(d)).
Detection of Low Tire Pressure Within Ten Minutes
    The June 2002 final rule specified performance requirements for the 
TPMS to detect when tire pressure drops below a specified level and to 
then illuminate a telltale mounted on the instrument panel. Under S6(e) 
of the standard, the inflation pressure in a tire or tires was to be 
reduced to the specified level, depending on the option selected by the 
manufacturer. Paragraph S6(f) stated that the vehicle is then driven at 
any speed between 50 km/hr and 100 km/hr, and the TPMS telltale must 
illuminate within 10 minutes after the vehicle has reached 50 km/hr.
    The Delphi petition raised a concern regarding the ability of the 
TPMS, in certain cases, to detect under-inflation within 10 minutes, as 
required by FMVSS No. 138 S4.2.2(a) and the related test procedure at 
S6(f). Delphi stated that in most cases, the TPMS should detect under-
inflation within the June 2002 final rule's 10-minute time limit; 
however, the petitioner asserted that certain periods of non-linear 
driving (e.g., sudden start-ups, sudden decelerations, shifting weight 
conditions) could impact the rolling of a vehicle's tires on the road, 
and thereby delay the TPMS's detection of tire

[[Page 55912]]

under-inflation. If such driving conditions constitute a sizable 
portion of the standard's testing time, the petitioner argued that the 
TPMS may fail to illuminate within the allotted 10-minute detection 
time period. Delphi contended that this variance, based upon real world 
conditions, could render the compliance test unobjective and 
unrepeatable. Consequently, Delphi petitioned NHTSA to revise S4.2.2 
and S6(f) to specify that the calculation of the 10-minute driving time 
for detection of significant tire under-inflation and illumination of 
the TPMS telltale will occur after not more than ten minutes of 
straight line, smooth driving.
    The Alliance petition argued that the June 5, 2002 final rule for 
TPMS lacked specificity in its test procedures, thereby causing the 
standard not to be objective. Although the TPMS rule specified ambient 
temperature, test surface, test weight, and vehicle speed, the Alliance 
petition argued that the rule fails to specify other essential 
parameters for the compliance test, such as whether the vehicle is to 
be driven on a straight or curved road, or whether there are any 
constraints on acceleration, braking, and steering inputs during 
testing. The Alliance argued that without specific direction regarding 
how these inputs will be controlled during compliance testing, 
manufacturers could never be sure that their vehicles would pass 
NHTSA's tests, because they could not predict what driving conditions 
would be used by the agency to verify compliance. Consequently, the 
Alliance recommended revision of the final rule's test procedure to 
require that a minimum of eight minutes cumulatively (although not 
continuously) of the total 10-minute detection time under the standard 
be driven on smooth, dry, level, and straight segments of roadway.
    These arguments regarding the specificity of the test procedures 
for TPMS warning lamp activation are similar to those raised about 
calibration test procedures. We again reiterate that, to provide an 
appropriate degree of safety, TPMSs must be designed so that they 
function properly under a full range of normal driving conditions, and 
vehicle manufacturers must ensure that their TPMSs function properly 
across the full range of such conditions.
    In order to ensure that our test procedures for detection of low 
tire pressure reflect normal driving situations and to ensure 
objectivity, we are proposing to incorporate the following elements in 
paragraphs S5 and S6 of the NPRM:
    (1) The road test surface for compliance testing would be any 
portion of the Southern Loop of the Treadwear Course defined in 
Appendix A and Figure 2 of 49 CFR 575.104 (See S5.2); and
    (2) We are proposing a new paragraph entitled System detection 
phase, which would specify that the vehicle will be driven in one 
direction up to 7 minutes cumulatively (not necessarily continuously) 
within the speed range of 50-100 km/h, or until the low tire pressure 
telltale illuminates, whichever occurs first. Time would not accumulate 
during periods when the brake pedal is applied. If the telltale does 
not illuminate during that period, vehicle direction would be reversed, 
and the vehicle would be driven an additional period of time up to a 
total of 10 minutes (counting both directions), or until the low tire 
pressure telltale illuminates. (See S6(f)).
Inflation Pressure
    As discussed earlier, NHTSA is proposing to require vehicles to 
comply with the TPMS standard with the tires that are installed on the 
vehicle at the time of initial sale.\38\
---------------------------------------------------------------------------

    \38\ In most cases, vehicles are equipped with four tires of the 
same size. However, in some cases, vehicle manufacturers or dealers 
may install different size tires on different axles. We are 
proposing that the TPMS must comply with the standard in those cases 
as well.
---------------------------------------------------------------------------

    We are proposing that vehicles must meet the standard when tested 
at any weight between the lightly loaded vehicle weight (LLVW) and the 
GVWR. We believe the TPMS should operate properly at all vehicle 
weights within the likely load range, and this requirement should not 
impose a burden on vehicle manufacturers.
    Under the proposed test procedures, the vehicle's tires would be 
inflated to the vehicle manufacturer's recommended cold tire inflation 
pressure at GVWR, as specified on the vehicle placard or the tire 
information label, regardless of the test weight. We are proposing this 
approach for two reasons. First, as discussed in further detail in the 
next section, we expect that consumers would consult the vehicle 
placard or tire inflation pressure label in order to obtain the 
recommended inflation pressure for their tires, and based upon new 
regulatory requirements, the placard or label will include only a 
single tire size and the recommended inflation pressure for that tire 
size at GVWR. In addition, most consumers generally do not increase or 
decrease their tire inflation pressure every time they change the 
amount of load they are carrying.
Reset Inflation Pressures
    Paragraph S6(a) of FMVSS No. 138 in the June 5, 2002 final rule 
stated that the vehicle's tires would be inflated to the manufacturer's 
recommended cold inflation pressure for the applicable vehicle load 
conditions specified in paragraph S5.3.1 of the standard (i.e., at the 
vehicle's lightly loaded vehicle weight and at its GVWR). Paragraph 
S6(c) of the standard stated that the TPMS would be reset in accordance 
with the instructions specified in the vehicle owner's manual.
    The Volkswagen petition stated that for some vehicles, the 
manufacturer specifies distinct tire pressures for fully-loaded and 
partially-loaded vehicles to provide optimum ride, handling, and 
occupant comfort. Volkswagen stated that its direct TPMS does not have 
a vehicle loading or weight sensor, so the system must be reset 
manually to accommodate the different tire pressures that correspond to 
current vehicle loading conditions. Volkswagen sought confirmation that 
the testing procedure under section S6(c) of the standard will include 
programming or setting the TPMS for the applicable vehicle loading 
condition.
    As we explained when we adopted new tire information requirements 
in late 2002 (see 67 FR 69600, 69610, November 18, 2002), we anticipate 
that consumers will increasingly rely upon the tire information found 
on the vehicle placard or tire inflation pressure label as their 
primary source for tire pressure information. A primary reason for this 
assumption is that effective September 1, 2004, FMVSS No. 110, Tire 
Selection and Rims, will require the vehicle placard (and optional tire 
inflation pressure label) to specify only one tire size and one 
inflation pressure appropriate for the maximum loaded vehicle weight, 
which must be applicable to the original tires installed on the vehicle 
at the time of initial vehicle sale.\39\ Beginning September 1, 2004, 
that standard will apply to all motor vehicles with a GVWR of 4,536 kg 
or less, except motorcycles.\40\
---------------------------------------------------------------------------

    \39\ See 68 FR 33655 (June 5, 2003).
    \40\ FMVSS No. 120, Tire Selection and Rims for Motor Vehicles 
Other Than Passenger Cars, presently applies to multi-purpose 
passenger vehicles (MPVs), trucks, and buses. Currently, FMVSS No. 
120 requires tire information either on the vehicle's certification 
label or on a separate label located in the same vicinity as the 
certification label. The label must provide the tire size 
designation and the recommended cold inflation pressure for those 
tires appropriate for the vehicle's front and rear gross axle weight 
ratings. FMVSS No. 120 does not require that the tire size installed 
on the vehicle and the inflation pressure for those tires be listed. 
However, beginning September 1, 2004, the tire labeling requirements 
of FMVSS No. 110 will apply also to those types of vehicles 
currently covered under FMVSS No. 120.

---------------------------------------------------------------------------

[[Page 55913]]

    Therefore, NHTSA is proposing to use only the vehicle 
manufacturer's recommended inflation pressure required to be provided 
under FMVSS No. 110 when testing for compliance. Most consumers will 
not add or reduce their tire inflation pressure every time they change 
the amount of load they are carrying, nor are they likely to 
recalibrate their TPMS in such situations. NHTSA has drafted paragraph 
S6(a) of the standard in the NPRM to reflect this approach.
    As noted previously, NHTSA is proposing to require vehicles to meet 
the requirements of the standard at any weight between LLVW and GVWR. 
NHTSA would follow the entire proposed test procedures section (S6), 
including paragraph S6(c), which states that the TPMS will be reset in 
accordance with the instructions specified in the vehicle owner's 
manual, to the extent that such a reset is consistent with the 
discussion above.
    The Delphi petition requested a further change to paragraph S6(c) 
of the June 5, 2002 standard. It requested the addition of language 
stating that as part of the testing procedures, the system will be 
reset and recalibrated, as explained in the vehicle's owner's manual. 
According to Delphi, recalibration may be necessary in certain 
instances, for example, to reflect changes in rolling radius or other 
characteristics accompanying a new replacement tire.
    We find it unnecessary to alter paragraph S6(c) of the NPRM to add 
language regarding the need for system calibration after reset, because 
the next sequential step in the proposed testing procedure (S6(d)) 
specifies a calibration process.
5. System Disablement
    The June 2002 final rule did not permit disablement of the TPMS, as 
it is the agency's normal practice not to allow safety systems to be 
disabled. Paragraphs S4.2.1 and S4.2.2 stated that the TPMS telltale 
must continue to illuminate as long as any of the vehicle's tires is 
experiencing under-inflation at the level specified under each option 
when the ignition locking system is in the ``On'' (``Run'') position. 
The preamble to the TPMS final rule specifically stated that NHTSA 
decided to prohibit any control that automatically disables the TPMS 
under any condition, dismissing arguments for even temporary 
disablement of the system.
    The issue of system disablement was raised in the petitions of both 
Porsche and the Alliance. In keeping with its own planned direct TPMS, 
Porsche asked the agency to reconsider its position on system 
disablement to permit a TPMS automatically to disable and then 
reactivate itself when it encounters confusing signals. The Porsche-
designed TPMS would illuminate a yellow telltale and text such as 
``system not active--brief disturbance'' when one of the following 
situations is encountered: (1) When the customer transports snow tires 
on rims with wheel sensors in the trunk when driving to the tire shop; 
(2) when a full-size spare tire without a wheel sensor is installed on 
the vehicle; (3) when the vehicle is in an area of considerable high 
frequency density; and (4) when components of the system are damaged. 
Porsche's suggestion in this regard is similar to the request made by 
the Alliance that the TPMS be allowed to indicate a system malfunction.
    The agency acknowledged in the June 5, 2002 final rule that all 
technology has limitations, and situations may arise in which the TPMS 
may not function properly. 67 FR 38704, 38730. However, while 
acknowledging such limitations, we are concerned that allowing system 
disablement in specified situations would remove manufacturers' 
incentives to improve the TPMS technology in order to overcome such 
limitations. Consequently, rather than permitting disablement of the 
TPMS in such instances such as those described by Porsche, NHTSA hopes 
that additional improvements in technology may overcome these instances 
of system malfunction. Although under the NPRM we are proposing to 
require manufacturers to certify TPMSs to the requirements of S4 of the 
standard, NHTSA has designed its proposed test conditions and 
procedures in S5 and S6 so as to avoid these anomalous situations.
    In general, the types of situations described by Porsche for which 
it requests system disablement are very different from the sort of 
voluntary and active disablement by the vehicle operator which the 
agency had considered and addressed previously. Instead, most 
situations raised by the petitioner are more akin to instances of TPMS 
malfunction, which are infrequent events that may be beyond the control 
of the vehicle operator. As discussed in Section III.C.1 above, the 
agency is proposing to require the TPMS to indicate a system 
malfunction to the vehicle operator.
    We continue to believe as a general matter that it would be 
inappropriate to permit any manual or automatic disablement of the 
TPMS. However, should the unusual events cited above occur, 
manufacturers would be required to alert the driver regarding 
impairment of the TPMS through a system malfunction warning.
    The Alliance petition asked the agency to revise the TPMS standard 
to permit one instance in which an indirect or hybrid TPMS may be 
disabled temporarily, namely when a differential or transfer case is 
locked. According to the Alliance, in such instances, relative wheel 
speed data are affected and, therefore, cannot be relied upon in making 
an inference of low inflation pressure. The Alliance stated that in 
such situations, the TPMS may provide false warnings if left activated.
    We note that the locking differential or transfer case scenario 
presented by the Alliance is quite different from the situations 
described in the Porsche petition, and we tentatively believe that it 
is not a good reason for TPMS disablement. Unlike the situations 
presented in the Porsche petition, which would be expected to be 
infrequent and of short duration, the locking transfer case situation 
presented by the Alliance could be encountered with some degree of 
frequency. It would not be appropriate to allow a vehicle to operate 
without a functioning TPMS when the transfer case is locked, since the 
situation can continue for extended periods, especially during the 
winter.
6. Instruction Manuals and Other Public Awareness Efforts
    In its petition, RMA asked NHTSA to revise the June 2002 TPMS 
rule's requirements for written instructions in owner's manuals under 
S4.5.1 and S4.5.2. The petitioner asked NHTSA to add language to make 
consumers aware that inclusion of a TPMS in a vehicle does not relieve 
them of their responsibility to routinely check tire pressure. RMA 
recommended the following language:

    The tire pressure monitoring system installed in your vehicle, 
required by government regulation, is not designed to warn you if 
the air pressure in one or more of your tires drops below the 
recommended cold inflation pressure (known as ``placard pressure'') 
established by the vehicle manufacturer.

    NHTSA does not believe that it is necessary to change the language 
as RMA has requested because paragraph S4.5, as included in the June 
2002 final rule, already contains an express statement regarding the 
importance of maintaining proper tire pressure. As proposed, paragraph 
S4.5 specifies mandatory language to be included in

[[Page 55914]]

the vehicle's owner's manual, including: ``Each tire, including the 
spare (if provided), should be checked monthly when cold and set to the 
inflation pressure recommended by the vehicle manufacturer.''
    Further, we believe that the language suggested by RMA would have 
the unintended effect of confusing consumers. The purpose of the TPMS, 
consistent with the TREAD Act, is to provide a safety warning to the 
vehicle operator when one or more tires become significantly under-
inflated. It is not designed to alert the driver whenever a tire 
deviates from placard pressure. RMA's recommended language could cause 
the consumer to doubt the capability of the TPMS to warn about any drop 
in air pressure. Consequently, we believe that the proposed language in 
S4.5 and long-standing agency advisories make clear that vehicle 
operators routinely should monitor and maintain proper tire pressure.
    The JATMA petition stated that the tire industry and automobile 
industry need to conduct an educational campaign to increase consumer 
awareness about the importance of maintaining proper tire pressure, and 
JATMA asked NHTSA to help promote such a campaign. NHTSA supports 
industry efforts to make consumers aware of the importance of 
maintaining adequate tire pressure. The agency has produced a tire 
safety brochure in conjunction with tire manufacturers and tire dealers 
that is titled ``Tire Safety, Everything Rides On It.'' This brochure 
is part of a public campaign to provide information on tire pressure 
monitoring, tire inspection, and the selection of replacement tires. 
The brochure also stresses the importance of tires to overall vehicle 
performance. (Please note that newly proposed owner's manual language 
related to replacement tires and the TPMS malfunction indicator is 
discussed under Section III.C.1 (Replacement Tires).)
7. Reserve Load
    The concept of ``tire reserve load'' refers to a tire's remaining 
load-carrying capabilities when a tire is inflated to a specific cold 
inflation pressure and the vehicle is loaded to a particular level. 
NHTSA did not address the issue of reserve load requirements in the 
TPMS rulemaking, and the June 2002 final rule for TPMS did not discuss 
tire reserve load in either the preamble or the regulatory text.
    JATMA expressed concern that if vehicle owners allow their tires to 
remain in an under-inflated condition for an extended period of time, 
these tires would deteriorate from fatigue and would be more likely to 
experience tire breakdown, even if the level of under-inflation were 
not great enough to trigger the TPMS warning. Consequently, JATMA asked 
the agency to set a reserve load of at least 10 percent.
    RMA stated that unless a sufficient reserve is built into placard 
pressure so that such pressure is sufficiently above the minimum 
required pressure, a TPMS detection level cannot safely be tied to 
placard pressure. RMA contended that without an adequate reserve load, 
tires operating at an inflation pressure almost 25-30% below placard 
pressure could have insufficient pressure to carry the vehicle's 
maximum load yet still not trigger the TPMS telltale.
    In order to address its concerns about reserve load, RMA filed a 
petition for rulemaking with the agency to amend FMVSS No. 110, Tire 
Selection and Rims, to establish a reserve load requirement, with an 
effective date consistent with the scheduled implementation of Part I 
of FMVSS No. 138. RMA recommended that the reserve load be determined 
based primarily on the vehicle placard pressure, the type of TPMS on 
the vehicle, and the load/pressure relationship for the selected tires, 
according to the Tire and Rim Association tables.
    We believe that the issue of reserve load is a tire issue most 
properly considered under FMVSS No. 110, as amended (see 67 FR 69600 
(November 18, 2002) and 68 FR 37981 (June 26, 2003)). NHTSA has issued 
Special Orders to both tire manufacturers and vehicle manufacturers 
requiring them to submit comprehensive information on real world tire 
failures and the tire reserve load associated with the tires and 
vehicles on which those failures occurred. We are in the process of 
analyzing the information received in response to these Special Orders 
to determine whether there is any correlation between tire reserve load 
and real world tire failures. A 1981 study of tire failure and reserve 
load did not demonstrate such a correlation.\41\ If new data indicate a 
sufficiently strong correlation, NHTSA will propose appropriate 
amendments to its standards.
---------------------------------------------------------------------------

    \41\ ``The Relationship Between Tire Reserve Load Percentage and 
Tire Failure Rate,'' Crash Avoidance Division, Office of Vehicle 
Safety Standards, NHTSA (81-09-NPRM-N01-002) (1981).
---------------------------------------------------------------------------

8. Temperature-Corrected Inflation Pressure
    The concept of ``temperature-corrected inflation pressure'' 
involves determining cold tire inflation pressure by compensating for 
the increased tire inflation pressure resulting from the rise in 
internal temperature caused by driving. The issue of temperature 
compensation was discussed in the preamble to the June 2002 final rule, 
but the agency decided not to specify any test procedure that 
explicitly relates to temperature correction. Therefore, the June 2002 
final rule did not include a procedure that compensates for pressure 
build-up that might occur due to increased temperature resulting from a 
vehicle being driven.
    JATMA's recommended language for revising S4.2 introduces the 
concept of ``temperature-corrected inflation pressure'' which it 
defines as ``an inflation pressure that has been corrected to the cold 
inflation pressure from the increased inflation pressure due to the 
rise of internal temperature caused by driving a vehicle.'' However, 
JATMA's petition did not provide any explanation for its recommendation 
related to ``temperature-corrected inflation pressure'' beyond the 
above language.
    NHTSA again declines to adopt the recommendation of the JATMA 
petition regarding temperature compensation. The procedure suggested by 
JATMA would introduce unnecessary complexity to the standard. NHTSA 
agrees that if a TPMS-equipped vehicle is tested immediately after the 
vehicle has been driven for some time, the stringency of the proposed 
standard's requirements could be reduced, because the tire from which 
pressure is released will be at 25 percent below the manufacturer's 
recommended cold tire inflation pressure, while the other tires may be 
up to 4 psi above that recommended pressure. However, nothing in the 
proposed standard requires NHTSA to test the performance of the TPMS 
immediately following calibration of the system. The agency plans to 
wait for up to an hour after calibration before releasing any pressure, 
which should allow all of the tires to cool down to approximately the 
ambient temperature. See paragraph S6(e).
9. Standardization of TPMS Parts
    In its petition, JATMA urged NHTSA to require standardization of 
TPMS parts and service methods, in order to increase the number of 
facilities that are available to consumers to service and maintain the 
TPMS. While NHTSA supports broad availability of vehicle maintenance 
and repair, JATMA has not provided any evidence to suggest that 
existing vehicle repair facilities would be unable to service TPMSs 
produced

[[Page 55915]]

pursuant to either the June 5, 2002 final rule or this NPRM. 
Consequently, we do not find it necessary or advisable to impose 
additional design restrictions on TPMS manufacturers.
10. Definitions
``Significant Under-Inflation''
    As published in the June 5, 2002 final rule, FMVSS No. 138 did not 
include a definition for the term ``significant under-inflation'' in 
paragraph S3, Definitions. The term is used in section 13 of the TREAD 
Act, which requires the Secretary of Transportation to issue ``a 
regulation to require a warning system in new motor vehicles to 
indicate to the vehicle operator when a tire is significantly under 
inflated.'' In recognition of the difficulty in determining precisely 
when tire under-inflation becomes ``significant,'' NHTSA chose to link 
the concept of ``significant under-inflation'' to a performance 
requirement that would provide a warning before significant safety 
concerns would be implicated. The TPMS standard also used the term as 
part of the required statement for inclusion in the owner's manual for 
vehicles covered under this standard.
    RMA petitioned the agency to define the term ``significant under-
inflation.'' Citing section 13 of the TREAD Act, RMA argued that 
NHTSA's approach of linking ``significant under-inflation'' to 
illumination of the TPMS telltale provides an inadequate and misleading 
message to the public.
    In reiteration of its comments submitted pursuant to the NPRM, RMA 
urged NHTSA to adopt RMA's definition of ``significant under-
inflation,'' meaning ``any inflation pressure that is less than the 
pressure required to carry the actual vehicle load on the tire per 
industry standards (or any pressure less than the pressure to carry the 
maximum vehicle load on the tire if the actual load is unknown).'' RMA 
reasoned that consumers should not be encouraged to believe that under-
inflated tires only require attention when the TPMS telltale 
illuminates. Instead, RMA argued that tires may require attention at an 
earlier point of pressure loss below the tire industry's recommended 
pressure. According to RMA, consumers should be discouraged from 
substituting reliance on TPMSs for regular maintenance and monitoring 
of their vehicles' tire pressure.
    In addition, JATMA's petition asked NHTSA to revise S4.2.1 of the 
standard to set the TPMS telltale's warning threshold at 20 percent 
below the vehicle manufacturer's recommended cold inflation pressure.
    We agree that it is important for consumers to maintain tire 
pressure in a manner consistent with vehicle specifications. In the 
June 2002 final rule, we explained our (still valid) reasoning for 
rejecting RMA's suggestion to tie the definition of ``significantly 
under-inflated'' to the load carrying capacity of the tire rather than 
the placard pressure (see 67 FR 38704, 38725). We declined to adopt 
this recommendation because the vehicle manufacturer's recommended 
pressure assumes loading at GVWR and also takes into consideration 
ride, handling, and other factors for safe vehicle operation. 
Therefore, we believe that it could be counterproductive for the agency 
to substitute this new frame of reference without a strong reason for 
doing so.
    RMA's petition for reconsideration did not provide any new 
justification for changing NHTSA's approach to defining ``significantly 
under-inflated'' or substituting load carrying capacity for placard 
pressure, beyond RMA's earlier arguments in its comments presented at 
the earlier NPRM stage. We continue to believe that under-inflation 
becomes significant when safe operation of the vehicle is threatened. 
As we explained in the June 2002 final rule, our new performance 
standard for tires requires that standard load P-metric tires be able 
to operate without failure when the tire is inflated to only 20 pounds 
per square inch (psi) and tested under full loading for at least 90 
minutes at 75 mph with no failure. We are proposing 20 psi as the 
minimum activation pressure for standard load P-metric tires under 
FMVSS No. 138, which is consistent with both the results of NHTSA's own 
tire testing and the values listed in the handbooks of the European 
Tyre and Rim Technical Organization (ETRTO), the Japanese Automobile 
Tyre Manufacturers Association (JATMA), and the Tire & Rim Association 
(T&RA). Consequently, we are not including RMA's recommendation as part 
of this NPRM.
    Regarding JATMA's request to amend the standard to set the TPMS 
telltale's warning threshold at 20 percent below the vehicle 
manufacturer's recommended cold inflation pressure, JATMA did not 
provide convincing evidence to support such a change, and we are not 
incorporating its suggestion.
``Small Volume Manufacturer''
    The June 2002 final rule excluded small volume manufacturers (SVMs) 
from compliance with the TPMS standard and associated reporting 
requirements during the phase-in period (i.e., November 1, 2003 to 
October 31, 2006). A SVM was defined under the standard as a 
manufacturer that produces fewer than 5,000 vehicles worldwide during 
the year. The SVM exclusion from compliance only applied to the three-
year phase-in period. According to the June 2002 final rule, beginning 
on November 1, 2006, new vehicles covered under Part II of the final 
rule would have had to be equipped with a TPMS that meets the 
requirements of FMVSS No. 138, regardless of the size of the vehicle 
manufacturer.
    The petitions of Ferrari S.p.A., Maserati S.p.A., and Vehicle 
Services Consulting, Inc. all asked the agency to modify the final 
rule's definition of ``small volume manufacturer'' to make it 
consistent with the definition of SVM in the agency's final rule for 
advanced air bags under FMVSS No. 208 (66 FR 65375, Dec. 18, 2001). 
Specifically, the petitioners requested a revision to paragraph S7.6 of 
the standard to exclude from the phase-in requirements those 
manufacturers that produce or assemble fewer than 5,000 vehicles 
annually for sale in the United States.
    We note that the agency strives for consistency in its regulations 
to the extent possible, but the complexity of technical requirements 
and their safety implications may vary considerably in the context of 
different rulemakings. Thus, provisions for implementation of one rule 
may not be appropriate for implementation of another. Therefore, we 
retain our discretion regarding how we may structure phase-in 
requirements for small volume manufacturers and will make such 
determinations on a case-by-case basis.
    However, we agree with the petitioners that in the case of the TPMS 
rule, it would be appropriate to grant the request to modify the 
definition of SVM so as to extend the exclusion from the phase-in 
requirements to manufacturers that produce fewer than 5,000 vehicles 
annually for sale in the United States. The TPMS standard will 
necessitate a change in vehicle design, and the United States is the 
only country that currently has such a standard. Consequently, NHTSA is 
proposing to change the way in which we define SVMs for phase-in 
purposes under S7.6 of the NPRM, moving from a 5,000 vehicle 
calculation based upon worldwide production to one of 5,000 vehicles 
produced for the U.S. market. We note that in the NPRM, we are 
proposing a modified phase-in schedule (S7), to which paragraph S7.6 is 
related.
``Tire Pressure Monitoring System''
    The June 2002 final TPMS rule defined ``tire pressure monitoring

[[Page 55916]]

system'' as a system that detects when one or more of a vehicle's tires 
are under-inflated and illuminates a low tire pressure warning 
telltale. 67 FR 38704, 38746.
    RMA petitioned NHTSA to modify the final rule's definition of the 
term ``tire pressure monitoring system'' to delete that portion of the 
definition stating that the TPMS ``detects when one or more of a 
vehicle's tires are under-inflated.'' RMA stated that its 
recommendation is intended to make clear to vehicle operators that 
TPMSs do not activate automatically whenever a tire experiences any 
under-inflation, but only when under-inflation reaches a certain level 
consistent with available technology and current policy.
    In drafting the NPRM, NHTSA did not incorporate RMA's recommended 
modification of the definition of ``tire pressure monitoring system.'' 
Although it is true that a TPMS will not alert a vehicle operator as 
soon as a tire deviates from recommended placard pressure, the original 
definition did not state that a vehicle's tires are properly inflated 
until the moment the telltale illuminates. However, to further minimize 
any possible confusion, we have added the word ``significantly'' before 
the word ``under-inflated'' in the definition of ``tire pressure 
monitoring system.''
11. Alternative Systems
    As noted earlier, section 13 of the TREAD Act required the 
Secretary of Transportation to issue a regulation requiring a warning 
system in new motor vehicles that indicates to the operator when a tire 
is significantly under-inflated (a responsibility delegated to NHTSA). 
Based upon this requirement, the June 2002 final rule stated in 
paragraph S4.3 that the TPMS must include a low tire pressure-warning 
telltale that is mounted inside the occupant compartment in front of 
and in clear view of the driver.
    Aviation Upgrade Technologies submitted a petition for 
reconsideration seeking to modify the TPMS standard so as to permit use 
of its valve cap system for monitoring tire pressure, which does not 
include a telltale mounted inside the occupant compartment. The 
petitioner's system is external to the vehicle, being located on the 
valve stem of each tire, and it is designed to constantly flash a red 
light whenever tire pressure drops by 4 psi or more. Aviation Upgrade 
Technologies indicated that the wheel rim-mounted TPMS telltale would 
alert a driver of a tire with low pressure before that person enters 
and starts the vehicle, if a tire loses air pressure while the vehicle 
is not in operation. The petitioner also stated that when a wheel-
mounted telltale illuminates while the vehicle is in operation, the 
driver may be alerted by fellow motorists who see the illuminated 
telltale and warn the driver.
    The petitioner made a number of claims as to why its system is 
superior to the TPMSs permitted under the June 2002 final rule, 
including the significantly lower cost of its system, ease of 
installation and self-calibration features, ease of maintenance, its 
efficacy with all types of tires and rims, and its suitability for use 
on both new and used vehicles.
    In drafting this NPRM, we decided not to propose language to 
accommodate Aviation Upgrade Technologies' system for the following 
reasons. First, we believe that the language of and the safety need 
addressed by section 13 of the TREAD Act would be best satisfied by 
requiring that the TPMS warning display be inside the motor vehicle in 
order to indicate to the driver when a tire is significantly under-
inflated. We believe that external TPMS warning indicators do not 
provide a clear, timely, and effective safety warning, as compared to 
TPMS indicators in the vehicle's occupant compartment.
    Specifically, TPMSs with external indicators cannot provide a 
warning to the driver about low tire inflation pressure while the 
vehicle is in operation, which is the most critical time period from a 
safety perspective. If a vehicle developed a significant pressure loss 
while it is being driven, the driver would not receive a prompt warning 
from the system and is unlikely to be aware of the under-inflation 
problem. We do not believe, as asserted in the Aviation Upgrade 
Technologies petition, that reliance on possible gestures or other 
signals from persons in passing vehicles would provide an adequate 
safety warning in those situations.
    Even in those cases in which the vehicle is stopped, we believe 
that external TPMS warning indicators would not provide as effective a 
warning as a TPMS telltale inside the occupant compartment. People 
routinely do not walk around their vehicle prior to driving, so it is 
likely that many drivers would miss the message provided when there is 
an under-inflated tire. Therefore, we believe that valve cap devices 
would not provide an adequate warning to the driver.
    Second, NHTSA also finds benefit to the centralization of warning 
indicators in a single, highly visible location, where they can provide 
important safety-related information to the driver. Historically, NHTSA 
has required safety warnings to be provided to the vehicle operator 
inside the vehicle.
    Therefore, we are not accommodating TPMSs that do not include an 
on-board telltale as part of this NPRM.

IV. Benefits

    In preparing its June 5, 2002 final rule, NHTSA prepared a Final 
Economic Analysis (FEA), which was placed in the docket.\42\ In that 
document, we discussed the costs and benefits of both the four-tire, 
25-percent option and the one-tire, 30-percent option incorporated in 
the final rule. However, in Public Citizen, Inc. v. Mineta, the Second 
Circuit determined that the TREAD Act requires TPMSs to be four-tire 
systems and invalidated the one-tire, 30-percent option. Accordingly, 
that option has not been included in this NPRM.
---------------------------------------------------------------------------

    \42\ Docket No. NHTSA-2000-8572-216.
---------------------------------------------------------------------------

    Although the FEA included analyses related to TPMSs with a four-
tire, 25-percent under-inflation detection capability (the same 
performance standard proposed in this NPRM), circumstances have changed 
to a certain extent since the June 2002 final rule. New technologies 
are emerging (e.g., batteryless direct TPMSs that could greatly reduce 
maintenance costs for such systems), and new requirements have been 
proposed (e.g., requirement for a TPMS malfunction indicator). 
Accordingly, the agency has prepared a new Preliminary Regulatory 
Impact Analysis (PRIA) to accompany this proposed rule for tire 
pressure monitoring systems. The PRIA has been submitted to the Docket 
under the docket number for this notice.
    The purpose of the PRIA is to reassess the costs and benefits of 
TPMS requirements, particularly in light of our proposed resolution of 
the replacement tire issue and the proposed requirement for a TPMS 
malfunction indicator. (The PRIA states that incorporation of a TPMS 
malfunction indicator may save an additional two equivalent lives, 
assuming a one-percent malfunction rate for replacement tires.) The 
PRIA examines various technologies suitable for compliance with the 
proposed standard, as well as additional regulatory alternatives 
considered by the agency. It also discusses the uncertainties analyses 
and sensitivities analyses conducted by the agency as part of the PRIA, 
per OMB Circular A-4, Regulatory Analysis, issued September 2003.
    The following discussion summarizes the benefits associated with 
this NPRM and its proposed four-tire, 25-percent

[[Page 55917]]

requirement. Estimates of monetary impacts (both in the section IV. 
Benefits and section V. Costs) are presented using a 3% discount rate; 
however, the PRIA also presents these impacts using a 7% discount rate.
    The agency notes that the PRIA estimates 90% confidence bounds for 
many of the benefit and cost statistics. Those bounds reflect a 90% 
certainty level that the value is within that range (both for a 3% and 
a 7% discount rate). However, to simplify the discussion here, we are 
presenting the mean values for the benefit estimates in this section 
and the cost estimates in the next section, with the ranges below 
reflecting differences in the mean values based upon manufacturers' 
technology selection. The mean values are our best estimates. Please 
consult the PRIA for a more complete discussion of benefits and costs. 
The full ranges of benefits and costs, as well as their 90% confidence 
bounds, can be found in the PRIA's uncertainty analysis (Chapter X).
    Under-inflation of tires affects the likelihood of many different 
types of crashes. These include crashes which result from: (1) Skidding 
and/or losing control of the vehicle in a curve, such as a highway off-
ramp, or in a lane-change maneuver; (2) hydroplaning on a wet surface, 
which can cause increases in stopping distance and skidding or loss of 
control; (3) increases in stopping distance; (4) flat tires and 
blowouts, and (5) overloading the vehicle. In assessing the impact of 
this proposal on those crashes, the agency assumes that 90 percent of 
drivers will respond to a low tire pressure warning by re-inflating 
their tires to the placard pressure.
    Based upon this assumption and depending upon the specific 
technology chosen for compliance, the agency estimates that the total 
quantified safety benefits from reductions in crashes due to skidding/
loss of control, stopping distance, and flat tires and blowouts will be 
119-121 fatalities prevented and 8,373-8,568 injuries prevented or 
reduced in severity each year, if all light vehicles met the TPMS 
requirement.
    Further, NHTSA anticipates additional economic benefits from the 
standard due to improved fuel economy, longer tread life, property 
damage savings, and travel delay savings. Correct tire pressure 
improves a vehicle's fuel economy. Based upon data provided by 
Goodyear, we have determined that a vehicle's fuel efficiency is 
reduced by one percent for every 2.96 psi that its tires are below the 
placard pressure. The agency estimates that if all light vehicles met 
the TPMS requirement, vehicles' higher fuel economy would translate 
into an average discounted value of $19.07-$23.08 per vehicle over the 
lifetime of the vehicle, depending upon the specific technology chosen 
for compliance.
    Correct tire pressure also increases a tire's tread life. Data from 
Goodyear indicate that, for every 1-psi drop in tire pressure, tread 
life decreases by 1.78 percent. NHTSA estimates that if all light 
vehicles met the proposed four-tire, 25-percent compliance requirement, 
average tread life would increase by 740 to 900 miles. The agency 
estimates that the average discounted value of resulting delays in new 
tire purchases would be $3.42-$4.24 per vehicle, depending upon the 
specific technology chosen for compliance.
    To the extent that TPMSs provide improvements related to stopping 
distance, blowouts, and loss of control in skidding, we expect that 
some crashes would be prevented and that in others, the severity of the 
impacts and the injuries that result would be reduced. As a related 
matter, we expect that property damage and travel delays would also be 
mitigated by these improvements. To the extent that crashes are 
avoided, both property damage and travel delay would be completely 
eliminated. Crashes that still occur, but do so at less serious impact 
speeds, would still cause property damage and delay other motorists, 
but to a lesser extent than they otherwise would have. The value of 
property damage and travel delay savings is estimated to be from $7.70-
$7.79 per vehicle.

V. Costs

    The PRIA also contains an in-depth analysis of the costs associated 
with the proposed TPMS standard. It analyzes the cost of different TPMS 
technologies, overall vehicle costs, maintenance costs, testing costs, 
and opportunity costs. The PRIA also analyzes the cost impact of the 
proposed requirement for a TPMS malfunction warning and its 
effectiveness in resolving the replacement tire issue.\43\ Again, 
please consult the PRIA for a more complete discussion of costs.\44\ 
The following points summarize the key tentative determinations related 
to costs.
---------------------------------------------------------------------------

    \43\ As noted in the discussion of benefits in the section 
immediately above, the following discussion of costs estimates 
monetary impacts using a 3% discount rate and provides the mean 
values for cost statistics based upon manufacturers' technology 
selection. The mean values are our best estimates. However, the PRIA 
provides a full range of costs, as well as their 90% confidence 
bounds, and it also presents these impacts using a 7% discount rate.
    \44\ With future technological development, it may become 
possible for indirect TPMSs and other types of systems to meet the 
proposed four-tire, 25-percent requirement. However, until such new, 
compliant TPMSs are developed, it is impossible to accurately 
estimate their costs.
---------------------------------------------------------------------------

    The agency examined three types of technology that manufacturers 
could use to meet the proposed TPMS requirement. Assuming that 
manufacturers will seek to minimize compliance costs, the agency 
expects that manufacturers would install hybrid TPMSs on the 67 percent 
of vehicles that are currently equipped with an ABS and direct TPMSs on 
the 33 percent of vehicles that are not so equipped. The highest costs 
for compliance would result if manufacturer installed direct TPMSs with 
an interactive readout of individual tire pressures that included 
sensors on all vehicle wheels. Thus, the agency estimates that the 
average incremental cost for all vehicles to meet the proposed 
requirement would range from $48.44-$69.89 per vehicle, depending upon 
the specific technology chosen for compliance. Since approximately 17 
million vehicles are produced for sale in the U.S. each year, the total 
annual vehicle cost would range from approximately $823-$1,188 million 
per year.
    The agency estimates that the net cost per vehicle [vehicle cost + 
maintenance costs + opportunity costs - (fuel savings + tread life 
savings + property damage and travel delay savings)] would be $26.63-
$100.25, assuming a one-percent TPMS malfunction rate for replacement 
tires. (Maintenance costs would be variable, depending upon whether the 
TPMS has batteries or is batteryless.) As noted above, the agency 
estimates the total annual vehicle cost for the fleet would be about 
$823-$1,188 million. Thus, using the same equation, the agency 
estimates the total annual net cost would be about $453-$1,704 million.
    NHTSA estimates that the net cost per equivalent life saved would 
be approximately $2.4-$9.1 million, depending upon the specific 
technology chosen for compliance. Placing 90% confidence bounds around 
the cost per equivalent life saved results in a range of $1.5-$14.5 
million.
    Net benefits-costs (benefits, including fatalities and injuries, 
valued in dollars minus costs) were also calculated per OMB Circular A-
4. The value of a statistical life is uncertain, and a wide range of 
values has been established in the literature. (In general, the 
statistical value of a life is valued in the range of $1 million to $10 
million per life, with a mean of $5.5 million.) For this analysis, we 
have examined values of

[[Page 55918]]

$3.5 million and $5.5 million, both of which fall within the range of 
accepted values. The mean value for net benefits-costs ranges from a 
net cost of $650 million to a net benefit of $599 million, depending 
upon the specific technology chosen for compliance. A 90 percent 
confidence bound around the net benefits-costs results in a range of a 
net cost of $1,156 million to a net benefit of $1,302 million.

VI. Regulatory Alternatives

    The proposed performance requirements contain two key variables: 
the number of tires monitored and the threshold level for providing 
tire pressure warnings. As noted elsewhere in this preamble, the Second 
Circuit determined in Public Citizen, Inc. v. Mineta that the TREAD Act 
unambiguously mandates TPMSs capable of monitoring each tire up to a 
total of four tires, effectively precluding any option with less than a 
four-tire detection capability. Further, the Court found that the 
agency had justification for adopting a four-tire, 25-percent option 
instead of the four-tire, 20-percent option proposed at an earlier 
stage of the rulemaking.
    Although NHTSA is proposing a 25 percent below placard threshold, 
technically, other threshold levels could also be established. 
Selecting an appropriate notification threshold level is a matter of 
balancing the safety benefits achieved by alerting consumers to low 
tire pressure against over-alerting them to the point of becoming a 
nuisance and causing consumers to ignore the warning, thus negating the 
potential of this proposal to produce safety benefits. Degradation in 
vehicle braking and handling performance does not become a significant 
safety issue at small pressure losses. There does not appear to be a 
specific threshold level at which benefits are maximized by a 
combination of minimum reduction in placard pressure and maximum 
response by drivers. NHTSA is confident that existing technology can 
meet the proposed 25 percent threshold. Setting a lower threshold might 
result in the opportunity for more savings if drivers' response levels 
were maintained; however, we are concerned that setting a lower 
threshold could result in a higher rate of non-response by drivers who 
regard the more frequent notifications as a nuisance. Current direct 
TPMS systems have a margin of error of 1-2 psi. That means, for 
example, that for a 30-psi tire, manufacturers would have to set the 
system to provide a warning when tires are 4 psi below placard if we 
were to require a 20 percent threshold. We tentatively conclude that 
this may be approaching a level at which a portion of the driving 
public would begin to regard the warning as a nuisance. We have not 
examined lower threshold levels in this analysis because we believe 
that the net impact of these offsetting factors (quicker notification, 
but lower frequency of driver response) is unknown and unlikely to 
produce a significant difference in safety benefits. We note that a 20 
percent 4-tire option was examined in the March 2002 analysis, and that 
the total benefit for the 20 percent threshold was about 15 percent 
higher than from the 25 percent threshold. However, that calculation 
assumed the same level of driver response for both thresholds. It is 
also possible that lower thresholds might limit technology and 
discourage innovation.
    Overall, we tentatively conclude that the 25 percent threshold 
adequately captures the circumstances at which low tire pressure 
becomes a safety issue. We also believe that this level would be 
acceptable to most drivers and would not be considered a nuisance to 
the point that it would be ignored by large numbers of drivers. We also 
believe there is no reason to examine higher thresholds (e.g., a 30 
percent threshold), since they would provide fewer benefits for similar 
costs.

VII. Public Participation

How Do I Prepare and Submit Comments?

    Your comments must be written and in English. To ensure that your 
comments are filed correctly in the Docket, please include the docket 
number of this document in your comments.
    Your comments must not be more than 15 pages long (see 49 CFR 
553.21). We established this limit to encourage you to write your 
primary comments in a concise fashion. However, you may attach 
necessary additional documents to your comments. There is no limit on 
the length of the attachments.
    Please submit two copies of your comments, including the 
attachments, to Docket Management at the address given under ADDRESSES.
    You may also submit your comments to the docket electronically by 
logging onto the Dockets Management System website at http://dms.dot.gov. Click on ``Help & Information,'' or ``Help/Info'' to 
obtain instructions for filing the document electronically.

How Can I Be Sure That My Comments Were Received?

    If you wish Docket Management to notify you upon its receipt of 
your comments, enclose a self-addressed, stamped postcard in the 
envelope containing your comments. Upon receiving your comments, Docket 
Management will return the postcard by mail.

How Do I Submit Confidential Business Information?

    If you wish to submit any information under a claim of 
confidentiality, you should submit three copies of your complete 
submission, including the information you claim to be confidential 
business information, to the Chief Counsel, NHTSA, at the address given 
above under FOR FURTHER INFORMATION CONTACT. In addition, you should 
submit two copies, from which you have deleted the claimed confidential 
business information, to Docket Management at the address given above 
under ADDRESSES. When you send a comment containing information claimed 
to be confidential business information, you should include a cover 
letter setting forth the information specified in our confidential 
business information regulation (49 CFR Part 512).

Will the Agency Consider Late Comments?

    We will consider all comments that Docket Management receives 
before the close of business on the comment closing date indicated 
above under DATES. To the extent possible, we also will consider 
comments that Docket Management receives after that date. If Docket 
Management receives a comment too late for us to consider it in 
developing the final rule, we will consider that comment as an informal 
suggestion for future rulemaking action.

How Can I Read The Comments Submitted by Other People?

    You may read the comments received by Docket Management at the 
address given under ADDRESSES. The hours of the Docket are indicated 
above in the same location.
    You also may see the comments on the Internet. To read the comments 
on the Internet, take the following steps:
    1. Go to the Docket Management System (DMS) Web page of the 
Department of Transportation (http://dms.dot.gov/).
    2. On that page, click on ``search.''
    3. On the next page (http://dms.dot.gov.search/), type in the four-
digit docket number shown at the beginning of this document. Example: 
If the docket number were ``NHTSA-1998-1234,'' you would type ``1234.'' 
After typing the docket number, click on ``search.''

[[Page 55919]]

    4. On the next page, which contains docket summary information for 
the docket you selected, click on the desired comments. Although the 
comments are imaged documents, instead of word processing documents, 
the ``pdf'' versions of the document are word searchable.
    Please note that even after the comment closing date, we will 
continue to file relevant information in the Docket as it becomes 
available. Further, some people may submit late comments. Accordingly, 
we recommend that you periodically check the Docket for new material.

VIII. Rulemaking Analyses and Notices

A. Executive Order 12866 and DOT Regulatory Policies and Procedures

    Executive Order 12866, ``Regulatory Planning and Review'' (58 FR 
51735, October 4, 1993), provides for making determinations whether a 
regulatory action is ``significant'' and therefore subject to OMB 
review and to the requirements of the Executive Order. The Order 
defines a ``significant regulatory action'' as one that is likely to 
result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more or 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or Tribal governments or 
communities;
    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs or the rights and obligations of recipients 
thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    Since the June 5, 2002 final rule, to which this NPRM is directly 
related, was determined to be economically significant, the agency 
prepared and placed in the docket a Final Economic Analysis (FEA). This 
proposed rule likewise was determined to be economically significant. 
As a significant notice, it was reviewed under Executive Order 12866. 
The rule is also significant within the meaning of the Department of 
Transportation's Regulatory Policies and Procedures. The agency has 
estimated that compliance with this proposed rule would cost $823--
$1,188 million per year, since approximately 17 million vehicles are 
produced for the United States market each year. Thus, this rule would 
have greater than a $100 million effect.
    As noted above, this NPRM was necessitated by the August 6, 2003 
opinion of the Court of Appeals for the Second Circuit in Public 
Citizen, Inc. v. Mineta. In that case, the court determined that the 
TREAD Act requires TPMSs to be four-tire systems, invalidated the one-
tire, 30-percent option contained in the June 5, 2002 final rule, and 
vacated the standard. As part of the NPRM, NHTSA also has responded 
substantively to issues raised in the 13 petitions for reconsideration 
filed in response to the June 5, 2002 final rule, the majority of which 
remain relevant even after that court decision. Accordingly, the agency 
has prepared and placed in the docket a Preliminary Regulatory Impact 
Analysis (PRIA) for this NPRM.

B. Regulatory Flexibility Act

    Pursuant to the Regulatory Flexibility Act (5 U.S.C. 601 et seq., 
as amended by the Small Business Regulatory Enforcement Fairness Act 
(SBREFA) of 1996), whenever an agency is required to publish a notice 
of rulemaking for any proposed or final rule, it must prepare and make 
available for public comment a regulatory flexibility analysis that 
describes the effect of the rule on small entities (i.e., small 
businesses, small organizations, and small governmental jurisdictions). 
The Small Business Administration's regulations at 13 CFR Part 121 
define a small business, in part, as a business entity ``which operates 
primarily within the United States.'' (13 CFR 121.105(a)). No 
regulatory flexibility analysis is required if the head of an agency 
certifies the rule will not have a significant economic impact on a 
substantial number of small entities. SBREFA amended the Regulatory 
Flexibility Act to require Federal agencies to provide a statement of 
the factual basis for certifying that a rule will not have a 
significant economic impact on a substantial number of small entities.
    NHTSA has considered the effects of this proposed rule under the 
Regulatory Flexibility Act. I certify that this proposed rule would not 
have a significant economic impact on a substantial number of small 
entities. The rationale for this certification is that currently there 
are only four small motor vehicle manufacturers (i.e., only four with 
fewer than 1,000 employees) in the United States that would have to 
comply with this proposed rule. These manufacturers would have to rely 
on suppliers to provide the TPMS hardware, and then they would have to 
integrate the TPMS into their vehicles.
    There are a few small manufacturers of recreational vehicles that 
would have to comply with this proposed rule. However, most of these 
manufacturers use van chassis supplied by the larger manufacturers 
(e.g., GM, Ford, or DaimlerChrysler) and could use the TPMSs supplied 
with the chassis. These manufacturers should not have to test the TPMS 
for compliance with this proposed rule since they should be able to 
rely upon the chassis manufacturer's incomplete vehicle documentation.
    Under the June 5, 2002 final rule, commenters expressed concerns 
about the final rule's impact upon aftermarket wheel and rim 
manufacturers, many of which are small businesses. These manufacturers 
were concerned that certain provisions of the final rule would have had 
the effect of restricting their ability to provide a full range of 
wheel and tire combinations to consumers, thereby negatively impacting 
their business. However, these concerns have largely been resolved by 
the agency's current proposal, which does not contain requirements for 
spare tires and aftermarket rims.
    We also analyzed the impact of this proposal on 14 identified 
suppliers of TPMS systems. However, of these companies, only three have 
fewer than 750 employees. Of these three companies, one (SmarTire) has 
its headquarters located outside of the United States, and another 
(Cycloid) has only ten employees and outsources the manufacturing of 
its products.
    In conclusion, the agency believes that this proposal would not 
affect a substantial number of small businesses.

C. Executive Order 13132 (Federalism)

    Executive Order 13132, ``Federalism'' (64 FR 43255, August 10, 
1999), requires NHTSA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' are defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.'' Under 
Executive Order 13132, the agency may not issue a regulation with 
Federalism implications, that imposes substantial direct compliance 
costs, and that is not required by statute, unless the Federal 
government provides the funds

[[Page 55920]]

necessary to pay the direct compliance costs incurred by State and 
local governments, the agency consults with State and local 
governments, or the agency consults with State and local officials 
early in the process of developing the proposed regulation. NHTSA also 
may not issue a regulation with Federalism implications and that 
preempts a State law unless the agency consults with State and local 
officials early in the process of developing the regulation.
    Although statutorily mandated, this proposed rule for TPMS was 
analyzed in accordance with the principles and criteria set forth in 
Executive Order 13132, and the agency determined that the rule would 
not have sufficient Federalism implications to warrant consultations 
with State and local officials or the preparation of a Federalism 
summary impact statement. This proposed rule would not have any 
substantial effects on the States, or on the current distribution of 
power and responsibilities among the various local officials.

D. Executive Order 12988 (Civil Justice Reform)

    Pursuant to Executive Order 12988, ``Civil Justice Reform'' (61 FR 
4729, February 7, 1996), the agency has considered whether this 
rulemaking would have any retroactive effect. This proposed rule does 
not have any retroactive effect. Under 49 U.S.C. 30103, whenever a 
Federal motor vehicle safety standard is in effect, a State may not 
adopt or maintain a safety standard applicable to the same aspect of 
performance which is not identical to the Federal standard, except to 
the extent that the State requirement imposes a higher level of 
performance and applies only to vehicles procured for the State's use. 
49 U.S.C. 30161 sets forth a procedure for judicial review of final 
rules establishing, amending, or revoking Federal motor vehicle safety 
standards. That section does not require submission of a petition for 
reconsideration or other administrative proceedings before parties may 
file a suit in court.

E. Executive Order 13045 (Protection of Children From Environmental 
Health and Safety Risks)

    Executive Order 13045, ``Protection of Children from Environmental 
Health and Safety Risks'' (62 FR 19855, April 23, 1997), applies to any 
rule that: (1) Is determined to be ``economically significant'' as 
defined under Executive Order 12866, and (2) concerns an environmental, 
health, or safety risk that the agency has reason to believe may have a 
disproportionate effect on children. If the regulatory action meets 
both criteria, the agency must evaluate the environmental health or 
safety effects of the planned rule on children, and explain why the 
planned regulation is preferable to other potentially effective and 
reasonably feasible alternatives considered by the agency.
    Although the TPMS rule has been determined to be an economically 
significant regulatory action under Executive Order 12866, the problems 
associated with under-inflated tires equally impact all persons riding 
in a vehicle, regardless of age. Consequently, this proposed rule does 
not involve decisions based upon health and safety risks that 
disproportionately affect children, as would necessitate further 
analysis under Executive Order 13045.

F. Paperwork Reduction Act

    Under the Paperwork Reduction Act of 1995 (PRA), a person is not 
required to respond to a collection of information by a Federal agency 
unless the collection displays a valid OMB control number. In the NPRM, 
it is proposed that each of the estimated 21 affected vehicle 
manufacturers provide one phase-in report for each of two years, 
beginning, at the earliest, in the fall of 2006.
    Pursuant to the June 5, 2002 TPMS final rule, the OMB has approved 
the collection of information ``Phase-In Production Reporting 
Requirements for Tire Pressure Monitoring Systems,'' assigning it 
Control No. 2127-0631 (expires 6/30/06). NHTSA has been given OMB 
clearance to collect a total of 42 hours a year (2 hours per 
respondent) for the TPMS phase-in reporting. However, until a new final 
rule is issued specifying phase-in reporting requirements, NHTSA will 
not collect any information pursuant to Control No. 2127-0631. If it 
should be necessary to do so, NHTSA may ask OMB for an extension of 
this clearance for an additional period of time.

G. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA), Public Law 104-113, (15 U.S.C. 272) directs the 
agency to evaluate and use voluntary consensus standards in its 
regulatory activities unless doing so would be inconsistent with 
applicable law or is otherwise impractical. Voluntary consensus 
standards are technical standards (e.g., materials specifications, test 
methods, sampling procedures, and business practices) that are 
developed or adopted by voluntary consensus standards bodies, such as 
the Society of Automotive Engineers (SAE). The NTTAA directs us to 
provide Congress (through OMB) with explanations when the agency 
decides not to use available and applicable voluntary consensus 
standards. The NTTAA does not apply to symbols.
    There are no voluntary consensus standards related to TPMS 
available at this time. However, NHTSA will consider any such standards 
as they become available.

H. Unfunded Mandates Reform Act

    Section 202 of the Unfunded Mandates Reform Act of 1995 (UMRA) 
requires federal agencies to prepare a written assessment of the costs, 
benefits, and other effects of proposed or final rules that include a 
Federal mandate likely to result in the expenditure by State, local, or 
tribal governments, in the aggregate, or by the private sector, of more 
than $100 million annually (adjusted for inflation with base year of 
1995 (so currently about $109 million)). Before promulgating a NHTSA 
rule for which a written statement is needed, section 205 of the UMRA 
generally requires the agency to identify and consider a reasonable 
number of regulatory alternatives and adopt the least costly, most 
cost-effective, or least burdensome alternative that achieves the 
objectives of the rule. The provisions of section 205 do not apply when 
they are inconsistent with applicable law. Moreover, section 205 allows 
the agency to adopt an alternative other than the least costly, most 
cost-effective, or least burdensome alternative if the agency publishes 
with the final rule an explanation of why that alternative was not 
adopted.
    This proposed rule would not result in the expenditure by State, 
local, or tribal governments, in the aggregate, or more than $109 
million annually, but it would result in an expenditure of that 
magnitude by vehicle manufacturers and/or their suppliers. In the June 
5, 2002 final rule, the precursor to the current proposal, the agency 
chose two compliance options (i.e., four-tire, 25-percent and one-tire, 
30-percent) in order to minimize compliance costs with the standard 
during the phase-in period.
    However, the Second Circuit in Public Citizen, Inc. v. Mineta 
struck down the one-tire, 30-percent option. Thus, in this proposed 
rule, NHTSA is proposing to adopt a four-tire, 25-percent requirement, 
which we believe is consistent with safety and the mandate in the TREAD 
Act, as fully discussed in the June 5, 2002 final rule. We note that in 
proposing a performance standard,

[[Page 55921]]

NHTSA has left the door open for an array of technologies that may be 
used to meet the standard's proposed requirements. With further TPMS 
development, we expect that vehicle manufacturers would have a number 
of technological choices that will provide broad flexibility to 
minimize their costs of compliance with the standard.

I. National Environmental Policy Act

    NHTSA has analyzed this rulemaking action for the purposes of the 
National Environmental Policy Act. The agency has determined that 
implementation of this action will not have any significant impact on 
the quality of the human environment.

J. Regulatory Identifier Number (RIN)

    The Department of Transportation assigns a regulation identifier 
number (RIN) to each regulatory action listed in the Unified Agenda of 
Federal Regulations. The Regulatory Information Service Center 
publishes the Unified Agenda in April and October of each year. You may 
use the RIN contained in the heading at the beginning of this document 
to find this action in the Unified Agenda.

K. Privacy Act

    Please note that anyone is able to search the electronic form of 
all comments received into any of our dockets by the name of the 
individual submitting the comment (or signing the comment, if submitted 
on behalf of an association, business, labor union, etc.). You may 
review DOT's complete Privacy Act Statement in the Federal Register 
published on April 11, 2000 (Volume 65, Number 70; Pages 19477-78), or 
you may visit http://dms.dot.gov.

List of Subjects in 49 CFR Parts 571 and 585

    Imports, Motor vehicle safety, Reporting and recordkeeping 
requirements, Tires.

    In consideration of the foregoing, NHTSA is proposing to amend 49 
CFR Parts 571 and 585 as follows:

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS

    1. The authority citation for Part 571 of Title 49 would continue 
to read as follows:

    Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166; 
delegation of authority at 49 CFR 1.50.

    2. Section 571.101 would be amended by revising paragraph S5.2.3 
and Table 2 to read as follows:


Sec.  571.101  Standard No. 101; Controls and displays.

* * * * *
    S5.2.3 Except for the Low Tire Pressure Telltale and the TPMS 
Malfunction Telltale, any display located within the passenger 
compartment and listed in column 1 of Table 2 that has a symbol 
designated in column 4 of that table shall be identified by either the 
symbol designated in column 4 (or symbol substantially similar in form 
to that shown in column 4) or the word or abbreviation shown in column 
3. The Low Tire Pressure Telltale (either the display identifying which 
tire has low pressure or the display which does not identify which tire 
has low pressure) and the TPMS Malfunction Telltale shall be identified 
by the appropriate symbol designated in column 4, or both the symbol in 
column 4 and the words in column 3. Additional words or symbols may be 
used at the manufacturer's discretion for the purpose of clarity. Any 
telltales used in conjunction with a gauge need not be identified. The 
identification required or permitted by this section shall be placed on 
or adjacent to the display that it identifies. The identification of 
any display shall, under the conditions of S6, be visible to the driver 
and appear to the driver perceptually upright.
* * * * *
BILLING CODE 4910-59-P

[[Page 55922]]

[GRAPHIC] [TIFF OMITTED] TP16SE04.009


[[Page 55923]]


[GRAPHIC] [TIFF OMITTED] TP16SE04.010

BILLING CODE 4910-59-C?>

[[Page 55924]]

    3. Section 571.138 would be added to read as follows:


Sec.  571.138  Standard No. 138; Tire pressure monitoring systems.

    S1 Purpose and scope. This standard specifies performance 
requirements for tire pressure monitoring systems (TPMSs) to prevent 
significant under-inflation of tires and the resulting safety problems.
    S2 Application. This standard applies to passenger cars, 
multipurpose passenger vehicles, trucks, and buses that have a gross 
vehicle weight rating of 4,536 kilograms (10,000 pounds) or less, 
except those vehicles with dual wheels on an axle, according to the 
phase-in schedule specified in S7 of this standard.
    S3 Definitions. The following definitions apply to this standard:
    Lightly loaded vehicle weight means unloaded vehicle weight plus 
the weight of a mass of 180 kg (396 pounds), including test driver and 
instrumentation.
    Tire pressure monitoring system means a system that detects when 
one or more of a vehicle's tires is significantly under-inflated and 
illuminates a low tire pressure warning telltale.
    Vehicle Placard and Tire inflation pressure label mean the sources 
of information for the vehicle manufacturer's recommended cold tire 
inflation pressure pursuant to section 571.110 of this Part.
    S4 Requirements.
    S4.1 General. To the extent provided in S7.1 through S7.3, each 
vehicle must be equipped with a tire pressure monitoring system that 
meets the requirements specified in S4 under the test conditions 
specified in S5 and the test procedures specified in S6 of this 
standard.
    S4.2 TPMS detection requirements. The tire pressure monitoring 
system must:
    (a) Illuminate a low tire pressure warning telltale not more than 
10 minutes after the inflation pressure in one or more of the vehicle's 
tires, up to a total of four tires, is equal to or less than either the 
pressure 25 percent below the vehicle manufacturer's recommended cold 
inflation pressure, or the pressure specified in the 3\rd\ column of 
Table 1 of this standard for the corresponding type of tire, whichever 
is higher;
    (b) Continue to illuminate the low tire pressure warning telltale 
as long as the pressure in any of the vehicle's tires is equal to or 
less than the pressure specified in S4.2(a), and the ignition locking 
system is in the ``On'' (``Run'') position, whether or not the engine 
is running. The telltale must be extinguished after the inflation 
pressure is corrected.
    S4.3 Low tire pressure warning telltale.
    S4.3.1 Each tire pressure monitoring system must include a low tire 
pressure warning telltale that:
    (a) Is mounted inside the occupant compartment in front of and in 
clear view of the driver;
    (b) Is identified by one of the symbols shown for the ``Low Tire 
Pressure Telltale'' in Table 2 of Standard No. 101 (49 CFR 571.101); 
and
    (c) Is illuminated under the conditions specified in S4.2.
    S4.3.2 In the case of a telltale that identifies which tire(s) is 
(are) under-inflated, each tire in the symbol for that telltale must 
illuminate when the tire it represents is under-inflated to the extent 
specified in S4.2.
    S4.3.3:
    (a) Except as provided in paragraph (b) of this section, each low 
tire pressure warning telltale must illuminate as a check of lamp 
function either when the ignition locking system is turned to the 
``On'' (``Run'') position when the engine is not running, or when the 
ignition locking system is in a position between ``On'' (``Run'') and 
``Start'' that is designated by the manufacturer as a check position.
    (b) The low tire pressure warning telltale need not illuminate when 
a starter interlock is in operation.
    S4.4 TPMS malfunction.
    (a) The vehicle shall be equipped with a tire pressure monitoring 
system that includes a telltale that illuminates whenever there is a 
malfunction that affects the generation or transmission of control or 
response signals in the vehicle's tire pressure monitoring system and 
extinguishes when the malfunction has been corrected. The vehicle's 
TPMS malfunction indicator shall meet the requirements of either 
S4.4(b) or S4.4(c).
    (b) Dedicated TPMS malfunction telltale
    The vehicle meets the requirements of S4.4(a) when equipped with a 
dedicated TPMS malfunction telltale that:
    (1) Is mounted inside the occupant compartment in front of and in 
clear view of the driver;
    (2) Is identified by the symbol shown for ``TPMS Malfunction 
Telltale'' in Table 2 of Standard No. 101 (49 CFR 571.101);
    (3) Is illuminated under the conditions specified in S4.4 for as 
long as the malfunction exists, whenever the ignition locking system is 
in the ``On'' (``Run'') position; and
    (4) (i) Except as provided in paragraph (ii), each dedicated TPMS 
malfunction telltale must be activated as a check of lamp function 
either when the ignition locking system is turned to the ``On'' 
(``Run'') position when the engine is not running, or when the ignition 
locking system is in a position between ``On'' (``Run'') and ``Start'' 
that is designated by the manufacturer as a check position.
    (ii) The dedicated TPMS malfunction telltale need not be activated 
when a starter interlock is in operation.
    (c) Combination low tire pressure/TPMS malfunction telltale
    The vehicle meets the requirements of S4.4(a) when equipped with a 
combined Low Tire Pressure/TPMS malfunction telltale that:
    (1) Meets the requirements of S4.2 and S4.3; and
    (2) Flashes for one minute upon detection of any condition 
specified in S4.4(a) after the ignition locking system is turned to the 
``On'' (``Run'') position. After the first minute, the telltale must 
remain continuously illuminated as long as the malfunction exists and 
the ignition locking system is in the ``On'' (``Run'') position. This 
flashing and illumination sequence must be repeated upon vehicle start-
up until the situation causing the malfunction has been corrected. The 
TPMS malfunction telltale must extinguish after the malfunction has 
been corrected.
    S4.5 Written instructions.
    (a) The owner's manual in each vehicle certified as complying with 
S4 must provide an image of the Low Tire Pressure Telltale symbol (and 
an image of the TPMS Malfunction Telltale symbol, if a dedicated 
telltale is utilized for this function) with the following statement in 
English:

    Each tire, including the spare (if provided), should be checked 
monthly when cold and inflated to the inflation pressure recommended 
by the vehicle manufacturer on the vehicle placard or tire inflation 
pressure label. (If your vehicle has tires of a different size than 
the size indicated on the vehicle placard or tire inflation pressure 
label, you should consult the appropriate section of this owner's 
manual to determine the proper tire inflation pressure.) When the 
low tire pressure telltale is illuminated, one or more of your tires 
is significantly under-inflated. You should stop and check your 
tires as soon as possible, and inflate them to the proper pressure. 
Driving on a significantly under-inflated tire causes the tire to 
overheat and can lead to tire failure. Under-inflation also reduces 
fuel efficiency and tire tread life, and may affect the vehicle's 
handling and stopping ability.
    Your vehicle has also been equipped with a TPMS malfunction 
telltale to indicate when the system is not operating properly. When 
the malfunction telltale is illuminated, the system may not be able 
to detect or signal

[[Page 55925]]

low tire pressure as intended. TPMS malfunctions may occur for a 
variety of reasons, including the installation of incompatible 
replacement tires on the vehicle. Always check the TPMS malfunction 
telltale after replacing one or more tires on your vehicle to ensure 
that the replacement tires are compatible with the TPMS.

    (b) The owner's manual may include additional information about the 
significance of the low tire pressure warning telltale illuminating, a 
description of corrective action to be undertaken, whether the tire 
pressure monitoring system functions with the vehicle's spare tire (if 
provided), and how to use a reset button, if one is provided.
    (c) If a vehicle does not come with an owner's manual, the required 
information shall be provided in writing to the first purchaser of the 
vehicle.
    S5 Test conditions.
    S5.1 Ambient temperature. The ambient temperature is between 0 
[deg]C (32 [deg]F) and 40 [deg]C (104 [deg]F).
    S5.2 Road test surface.
    Compliance testing is conducted on any portion of the Southern Loop 
of the Treadwear Test Course defined in Appendix A and Figure 2 of 
section 575.104 of this chapter. The road surface is dry during 
testing.
    S5.3 Vehicle conditions.
    S5.3.1 Test weight. The vehicle may be tested at any weight between 
its lightly loaded vehicle weight and its gross vehicle weight rating 
(GVWR) without exceeding any of its gross axle weight ratings.
    S5.3.2 Vehicle speed. The vehicle's TPMS is calibrated and tested 
at speeds between 50 km/h (31.1 mph) and 100 km/h (62.2 mph).
    S5.3.3 Rim position.
    The vehicle rims may be positioned at any wheel position, 
consistent with any related instructions or limitations in the vehicle 
owner's manual.
    S5.3.4 Stationary location.
    The vehicle's tires are shaded from direct sun when the vehicle is 
parked.
    S5.3.5 Brake pedal application. Driving time shall not accumulate 
during service brake application.
    S5.3.6 Range of conditions or test parameters.
    Whenever a range of conditions or test parameters is specified in 
this standard, the vehicle must meet applicable requirements when 
tested at any point within the range.
    S6 Test procedures.
    (a) Inflate the vehicle's tires to the cold tire inflation 
pressure(s) provided on the vehicle placard or the tire inflation 
pressure label.
    (b) With the vehicle stationary and the ignition locking system in 
the ``Lock'' or ``Off'' position, turn the ignition locking system to 
the ``On'' (``Run'') position or, where applicable, the appropriate 
position for the lamp check. The tire pressure monitoring system must 
perform a check of lamp function for the low tire pressure telltale as 
specified in paragraph S4.3.3 of this standard. If the vehicle is 
equipped with a separate TPMS malfunction telltale, the tire pressure 
monitoring system also must perform a check of lamp function as 
specified in paragraph S4.4(b)(4) of this standard.
    (c) If applicable, reset the tire pressure monitoring system in 
accordance with the instructions in the vehicle owner's manual.
    (d) System calibration/learning phase.
    (1) Drive the vehicle along any portion of the test course for 10-
15 minutes of cumulative time (not necessarily continuously).
    (2) Drive the vehicle in the opposite direction along the test 
course for 5-15 minutes of cumulative time (not necessarily 
continuously).
    (3) The sum of the total cumulative driving time under paragraphs 
S6(d)(1) and (2) shall not be less than 20 minutes.
    (e) Stop the vehicle and keep the vehicle stationary for up to one 
hour with the engine off. Deflate any combination of one to four tires 
until the deflated tire(s) is (are) at 7 kPa (1 psi) below the 
inflation pressure at which the tire pressure monitoring system is 
required to illuminate the low tire pressure warning telltale.
    (f) System detection phase.
    (1) Drive the vehicle for up to 7 minutes of cumulative time (not 
necessarily continuously) along any portion of the test course, or 
until the low tire pressure telltale illuminates, whichever occurs 
first.
    (2) If the telltale did not illuminate during the step in paragraph 
S6(f)(1), reverse direction on the course and drive the vehicle for an 
additional period of time up to a total cumulative time of 10 minutes 
(including the time in S6(f)(1), and not necessarily continuously), or 
until the low tire pressure telltale illuminates.
    (3) If the low tire pressure telltale did not illuminate, 
discontinue the test.
    (g) If the low tire pressure telltale illuminated during the 
procedure in paragraph S6(f), turn the ignition locking system to the 
``Off'' or ``Lock'' position. After a 5-minute period, turn the 
vehicle's ignition locking system to the ``On'' (``Run'') position. The 
telltale must illuminate and remain illuminated as long as the ignition 
locking system is in the ``On'' (``Run'') position.
    (h) Keep the vehicle stationary for a period of up to one hour with 
the engine off.
    (i) If the vehicle's TPMS has a manual reset feature, attempt to 
reset the system in accordance with instructions specified in the 
vehicle owner's manual prior to re-inflating the vehicle's tires. If 
the low tire pressure telltale illuminates, discontinue the test.
    (j) Inflate all of the vehicle's tires to the same inflation 
pressure used in paragraph S6(a). If the vehicle's tire pressure 
monitoring system has a manual reset feature, reset the system in 
accordance with the instructions specified in the vehicle owner's 
manual. Determine whether the telltale has extinguished. If necessary, 
drive the vehicle for a time period of up to 10 minutes.
    (k) The test may be repeated, using the test procedures in 
paragraphs S6(a) through (j), with any one, two, three, or four of the 
tires on the vehicle under-inflated.
    (l) TPMS malfunction detection.
    (1) Simulate one or more TPMS malfunction(s) by disconnecting the 
power source to any TPMS component, disconnecting any electrical 
connection between TPMS components, by simulating a TPMS sensor 
malfunction, or by installing a tire on the vehicle that is 
incompatible with the TPMS.
    (2) Turn the ignition locking system to the ``On'' (``Run'') 
position or, where appropriate, the position for lamp check. The TMPS 
malfunction telltale must illuminate in accordance with paragraph S4.4.
    (3) If the vehicle is equipped with a TPMS reset feature to 
extinguish the low tire pressure and/or malfunction telltale, reset the 
system according to the manufacturer's instructions. Verify that the 
TPMS continues to identify a system malfunction as specified in 
paragraph S4.4.
    (4) Restore the TPMS to normal operation, reset if necessary, and 
verify that the malfunction telltale is extinguished.
    S7 Phase-in schedule.
    S7.1 Vehicles manufactured on or after September 1, 2005, and 
before September 1, 2006. For vehicles manufactured on or after 
September 1, 2005, and before September 1, 2006, the number of vehicles 
complying with this standard must not be less than 50 percent of:
    (a) The manufacturer's average annual production of vehicles 
manufactured on or after September 1, 2002, and before September 1, 
2005; or
    (b) The manufacturer's production on or after September 1, 2005, 
and before September 1, 2006.

[[Page 55926]]

    S7.2 Vehicles manufactured on or after September 1, 2006, and 
before September 1, 2007. For vehicles manufactured on or after 
September 1, 2006, and before September 1, 2007, the number of vehicles 
complying with this standard must not be less than 90 percent of:
    (a) The manufacturer's average annual production of vehicles 
manufactured on or after September 1, 2003, and before September 1, 
2006; or
    (b) The manufacturer's production on or after September 1, 2006, 
and before September 1, 2007.
    S7.3 Vehicles manufactured on or after September 1, 2007. All 
vehicles manufactured on or after September 1, 2007 must comply with 
this standard.
    S7.4 Calculation of complying vehicles.
    (a) For purposes of complying with S7.1, a manufacturer may count a 
vehicle if it is certified as complying with this standard and is 
manufactured on or after (date to be inserted that is 60 days after 
date of publication of the final rule), but before September 1, 2006.
    (b) For purposes of complying with S7.2, a manufacturer may count a 
vehicle if it:
    (1)(i) Is certified as complying with this standard and is 
manufactured on or after (date to be inserted that is 60 days after 
date of publication of the final rule), but before September 1, 2007; 
and
    (ii) Is not counted toward compliance with S7.1; or
    (2) Is manufactured on or after September 1, 2006, but before 
September 1, 2007.
    S7.5 Vehicles produced by more than one manufacturer.
    S7.5.1 For the purpose of calculating average annual production of 
vehicles for each manufacturer and the number of vehicles manufactured 
by each manufacturer under S7.1 through S7.3, a vehicle produced by 
more than one manufacturer must be attributed to a single manufacturer 
as follows, subject to S7.5.2:
    (a) A vehicle that is imported must be attributed to the importer.
    (b) A vehicle manufactured in the United States by more than one 
manufacturer, one of which also markets the vehicle, must be attributed 
to the manufacturer that markets the vehicle.
    S7.5.2 A vehicle produced by more than one manufacturer must be 
attributed to any one of the vehicle's manufacturers specified by an 
express written contract, reported to the National Highway Traffic 
Safety Administration under 49 CFR Part 585, between the manufacturer 
so specified and the manufacturer to which the vehicle would otherwise 
be attributed under S7.5.1.
    S7.6 Small volume manufacturers. Vehicles manufactured during any 
of the two years of the September 1, 2005 through August 31, 2007 
phase-in by a manufacturer that produces fewer than 5,000 vehicles for 
sale in the United States during that year are not subject to the 
requirements of S7.1, S7.2, and S7.4.
    S7.7 Final-stage manufacturers and alterers. Vehicles that are 
manufactured in two or more stages or that are altered (within the 
meaning of 49 CFR 567.7) after having previously been certified in 
accordance with Part 567 of this chapter are not subject to the 
requirements of S7.1 through S7.2 and S7.4.

Tables to Sec.  571.138
[GRAPHIC] [TIFF OMITTED] TP16SE04.011

PART 585--PHASE-IN REPORTING REQUIREMENTS

    4. Proposed amendments to Part 585 were published on August 6, 
2003, that would consolidate phase-in reporting requirements for 
various standards (68 FR 46546). Consistent with that proposal, Part 
585 would be amended further, as follows:
    1. The authority citation for Part 585 of Title 49 would be added 
to read as follows:

    Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166; 
delegation of authority at 49 CFR 1.50.

    2. Subpart D would be revised to read as follows:
Subpart D--Tire Pressure Monitoring System Phase-in Reporting 
Requirements
Sec.
585.31 Scope.
585.32 Purpose.
585.33 Applicability.
585.34 Definitions.
585.35 Response to inquiries.
585.36 Reporting requirements.
585.37 Records.

[[Page 55927]]

585.38 Petition to extend period to file report.

Subpart D--Tire Pressure Monitoring System Phase-in Reporting 
Requirements


Sec.  585.31  Scope.

    This subpart establishes requirements for manufacturers of 
passenger cars, multipurpose passenger vehicles, trucks, and buses with 
a gross vehicle weight rating of 4,536 kilograms (10,000 pounds) or 
less, except those vehicles with dual wheels on an axle, to submit a 
report, and maintain records related to the report, concerning the 
number of such vehicles that meet the requirements of Standard No. 138, 
Tire pressure monitoring systems (49 CFR 571.138).


Sec.  585.32  Purpose.

    The purpose of these reporting requirements is to assist the 
National Highway Traffic Safety Administration in determining whether a 
manufacturer has complied with Standard No. 138.


Sec.  585.33  Applicability.

    This subpart applies to manufacturers of passenger cars, 
multipurpose passenger vehicles, trucks, and buses with a gross vehicle 
weight rating of 4,536 kilograms (10,000 pounds) or less, except those 
vehicles with dual wheels on an axle. However, this subpart does not 
apply to manufacturers whose production consists exclusively of 
vehicles manufactured in two or more stages, and vehicles that are 
altered after previously having been certified in accordance with part 
567 of the chapter. In addition, this subpart does not apply to 
manufacturers whose production of motor vehicles for the United States 
market is less than 5,000 vehicles in a production year.


Sec.  585.34  Definitions.

    Production year means the 12-month period between September 1 of 
one year and August 31 of the following year, inclusive.


Sec.  585.35  Response to inquiries.

    At any time prior to August 31, 2007, each manufacturer must, upon 
request from the Office of Vehicle Safety Compliance, provide 
information identifying the vehicles (by make, model, and vehicle 
identification number) that have been certified as complying with 
Standard No. 138. The manufacturer's designation of a vehicle as a 
certified vehicle is irrevocable.


Sec.  585.36  Reporting requirements.

    (a) General reporting requirements. Within 60 days after the end of 
the production years ending August 31, 2006 and August 31, 2007, each 
manufacturer must submit a report to the National Highway Traffic 
Safety Administration concerning its compliance with Standard No. 138 
(49 CFR 571.138) for its passenger cars, multipurpose passenger 
vehicles, trucks, and buses with a gross vehicle weight rating of less 
than 4,536 kilograms (10,000 pounds) produced in that year. Each report 
must--
    (1) Identify the manufacturer;
    (2) State the full name, title, and address of the official 
responsible for preparing the report;
    (3) Identify the production year being reported on;
    (4) Contain a statement regarding whether or not the manufacturer 
complied with the requirements of Standard No. 138 (49 CFR 571.138) for 
the period covered by the report and the basis for that statement;
    (5) Provide the information specified in paragraph (b) of this 
section;
    (6) Be written in the English language; and
    (7) Be submitted to: Administrator, National Highway Traffic Safety 
Administration, 400 Seventh Street, SW., Washington, DC 20590.
    (b) Report content.
    (1) Basis for statement of compliance. Each manufacturer must 
provide the number of passenger cars, multipurpose passenger vehicles, 
trucks, and buses with a gross vehicle weight rating of 4,536 kilograms 
(10,000 pounds) or less, except those vehicles with dual wheels on an 
axle, manufactured for sale in the United States for each of the three 
previous production years, or, at the manufacturer's option, for the 
current production year. A new manufacturer that has not previously 
manufactured these vehicles for sale in the United States must report 
the number of such vehicles manufactured during the current production 
year.
    (2) Production. Each manufacturer must report for the production 
year for which the report is filed: the number of passenger cars, 
multipurpose passenger vehicles, trucks, and buses with a gross vehicle 
weight rating of 4,536 kilograms (10,000 pounds) or less that meet 
Standard No. 138 (49 CFR 571.138).
    (3) Vehicles produced by more than one manufacturer. Each 
manufacturer whose reporting of information is affected by one or more 
of the express written contracts permitted by S7.5.2 of Standard No. 
138 (49 CFR 571.138) must:
    (i) Report the existence of each contract, including the names of 
all parties to the contract, and explain how the contract affects the 
report being submitted.
    (ii) Report the actual number of vehicles covered by each contract.


Sec.  585.37  Records.

    Each manufacturer must maintain records of the Vehicle 
Identification Number for each vehicle for which information is 
reported under Sec.  590.6(b)(2) until December 31, 2009.


Sec.  585.38  Petition to extend period to file report.

    A manufacturer may petition for extension of time to submit a 
report under this Part. A petition will be granted only if the 
petitioner shows good cause for the extension and if the extension is 
consistent with the public interest. The petition must be received not 
later than 15 days before expiration of the time stated in Sec.  
585.36(a). The filing of a petition does not automatically extend the 
time for filing a report. The petition must be submitted to: 
Administrator, National Highway Traffic Safety Administration, 400 
Seventh Street, SW., Washington, DC 20590.

    Issued: September 10, 2004.
Stephen R. Kratzke,
Associate Administrator for Rulemaking.
[FR Doc. 04-20791 Filed 9-10-04; 3:25 pm]
BILLING CODE 4910-59-P