Federal Motor Vehicle Safety Standards; Transmission Shift Position Sequence, Starter Interlock, and Transmission Braking Effect, 38040-38052 [05-13062]

Agencies

• National Highway Traffic Safety Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 70, Number 126 (Friday, July 1, 2005)]
[Rules and Regulations]
[Pages 38040-38052]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-13062]


=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[DOT Docket No. NHTSA-05-21401]
RIN: 2127-AI43


Federal Motor Vehicle Safety Standards; Transmission Shift 
Position Sequence, Starter Interlock, and Transmission Braking Effect

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

ACTION: Final rule.

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

SUMMARY: This document amends the starter interlock requirements of our 
safety standard on transmission shift position sequence, starter 
interlock, and transmission braking effect to clarify how the 
requirements apply to vehicles incorporating emerging technologies. The 
amendment is intended to facilitate the development of propulsion 
systems that conserve energy and reduce emissions by stopping the 
engine (internal combustion engine) when it is not needed. It is also 
intended to minimize the possibility of crashes in which a driver has 
mis-shifted into a forward or reverse gear and would be unprepared for 
the direction of motion by the vehicle when the engine restarts.

DATES: This final rule becomes effective December 28, 2005.
    Any petitions for reconsideration of today's final rule must be 
received by NHTSA not later than August 15, 2005.

ADDRESSES: Petitions for reconsideration should refer to the docket 
number for this section and be submitted to: Administrator, National 
Highway Traffic Safety Administration, 400 Seventh Street, SW., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: For non-legal issues, you may call Mr. 
William Evans, Office of Crash Avoidance Standards at (202) 366-2272. 
His FAX number is (202) 366-7002.
    For legal issues, you may call Ms. Dorothy Nakama, Office of the 
Chief Counsel at (202) 366-2992. Her FAX number is (202) 366-3820.
    You may send mail to both of these officials at National Highway 
Traffic Safety Administration, 400 Seventh St., SW., Washington, DC, 
20590.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Executive Summary
II. Notice of Proposed Rulemaking (NPRM)
III. Public Comments to the NPRM
IV. Public Comments and NHTSA's Response
    A. Requiring Reverse Creep Force in Vehicles that Allow the ICE 
to Stop and Start Automatically When the Vehicle's Shift Position is 
in Reverse
    B. Applicability to Vehicles Over 10,000 Pounds GVWR
    C. Specifying a Maximum Throttle Opening Regardless of Driver 
Throttle Input on Idle-Stop Systems During Automatic ICE Starting
    D. Requiring a Manual Override to Deactivate the Idle-Stop 
Feature
    E. Maximum Time Between Brake Pedal Release and Propulsion 
System Availability
    F. Leaving FMVSS No. 102 Unchanged and Placing New Requirements 
in a Separate Standard
    G. Use of the Term ``Driver Activation''
    H. ``Shift Position'' Versus ``Shift Lever Position''
    I. Clarification of When the ICE May Stop and Start
    J. Other Issues Raised in Response to the NPRM
    1. Minimum Creep Force Value of 1.5 Percent of GVWR.
    2. Applicability of the Phrase ``Brake Pedal Released'' to Air 
Brakes
    3. Requiring Creep Force in Reverse When the ICE is Both ``On'' 
and ``Off''
    4. Use of the Term ``Electric Motor'' in the Regulatory Text
    5. Use of the Term ``Battery'' in the Regulatory Text
V. Final Rule
VI. Statutory Bases for the Final Rule
VII. Effective Date
VIII. Regulatory Analyses and Notices
    A. Executive Order 12866; DOT Regulatory Policies and Procedures
    B. Executive Order 13132 (Federalism)
    C. Executive Order 13045 (Economically Significant Rules 
Affecting Children)
    D. Executive Order 12988 (Civil Justice Reform)
    E. Regulatory Flexibility Act
    F. National Environmental Policy Act
    G. Paperwork Reduction Act
    H. National Technology Transfer and Advancement Act
    I. Plain Language
    J. Regulation Identifier Number (RIN)

Regulatory Text

I. Executive Summary

    The existing starter interlock requirement of Federal Motor Vehicle 
Safety Standard (FMVSS) No. 102 (at S3.1.3) states ``the engine starter 
shall be inoperative when the transmission shift lever is in a forward 
or reverse drive position.'' The purpose of this requirement is to 
prevent injuries and death from the unexpected motion of a vehicle when 
the driver starts the vehicle with the transmission inadvertently in a 
forward or reverse gear. Two recently introduced vehicles, the Toyota 
Prius \1\ and the Honda

[[Page 38041]]

Insight \2\, are powered by hybrid/electric systems (the Toyota Hybrid 
System (THS) and Honda's Idle-stop Technology (IST)) that permit their 
gasoline engines to stop and restart automatically while the 
transmission shift lever is in a drive position.
---------------------------------------------------------------------------

    \1\ The Prius is an electric motor-powered vehicle assisted by 
an internal combustion engine (ICE). When the propulsion system is 
activated, the vehicle is powered by the electric motor. The ICE 
starts and runs when additional motive power is required or when 
electrical energy is needed to power the motor and/or to charge the 
propulsion batteries. The ICE is always running at speeds greater 
than 42 miles per hour. The Prius propulsion system exhibits creep 
force and is capable of propelling the vehicle in the normal travel 
mode in all forward and reverse drive gears even when the engine is 
stopped and behaves like a conventional ICE/automatic transmission-
equipped vehicle.
    \2\ The Insight is an ICE powered vehicle assisted by an 
electric motor and employs idle-stop technology. The electric motor 
provides assistance when additional motive power is required during 
acceleration. The ICE of the Insight automatically stops when the 
brake is applied and the vehicle is stopped. The Insight restarts 
when the brake is released. The idle-stop feature is not employed in 
Reverse and therefore, the ICE does not stop in Reverse. If the ICE 
is stopped in a forward gear and Reverse is selected, the ICE starts 
immediately, provided the service brake is applied.
---------------------------------------------------------------------------

    Each manufacturer asked us to interpret S3.1.3 as it applied to 
these new vehicles. In interpretation letters to Toyota (November 1, 
1999) and Honda (January 17, 2001), we concluded that S3.1.3 would not 
prohibit either system. In each case, we based our interpretation on a 
determination that the system met S3.1.3's underlying purpose of 
ensuring that the vehicle will not lurch forward or backward during 
driver activation of the engine starter because driver activation of 
the engine starter is inoperative when the transmission shift lever is 
in a drive position. We also noted that these new systems were more 
complex than those on vehicles that existed when S3.1.3 was first 
adopted, and that we planned to conduct rulemaking to clarify FMVSS No. 
102 as applied to emerging technologies. Pending completion of the 
rulemaking, we stated that we would interpret S3.1.3 as requiring that 
driver activation of the engine starter must be inoperative when the 
transmission shift lever is in a forward or reverse drive position.
    In the NPRM (68 FR 26269, May 15, 2003), we proposed to amend the 
regulatory text of FMVSS No. 102 to make it clear that the engine may 
start and stop automatically after the driver has activated the 
vehicle's propulsion system, when the transmission shift lever is in 
any forward gear. Under the proposed regulatory text, this was also 
permitted when the shift lever is in Reverse, but only if the vehicle's 
propulsion system provides, at least, a minimum creep force in Reverse 
when the engine is stopped, the accelerator is released and the 
propulsion system is activated.
    After carefully considering the public comments, we have decided to 
adopt a final rule with some changes from the proposal. This final rule 
amends S3.1.3 to accommodate these new technologies, while preserving 
the safety purpose of the standard. Although the creep force 
requirements proposed in the NPRM are not adopted in the final rule, 
the final rule addresses the same safety problems in a simpler way.
    With respect to vehicles with automatic transmissions, the rule 
makes it clear that, after activation of the vehicle's propulsion 
system by the driver, the engine may stop and restart automatically 
when the transmission shift position is in any forward drive gear. The 
rule prohibits the engine from automatically stopping in reverse gear. 
When the engine is automatically stopped in a forward drive shift 
position and the driver selects Reverse, the engine is permitted to 
restart automatically in Reverse if two conditions are satisfied. The 
first condition is that the engine must restart immediately whenever 
the service brake is applied. The second condition is that the engine 
does not start automatically if the service brake is not applied.
    The rule also provides, notwithstanding these limitations, that the 
engine may stop and start at any time after the driver has activated 
the vehicle's propulsion system if: (a) The vehicle's propulsion system 
can propel the vehicle in the normal travel mode in all forward and 
reverse drive gears without the engine operating, and (b) if the engine 
automatically starts while the vehicle is traveling at a steady speed 
and steady accelerator control setting, the engine does not cause the 
vehicle to accelerate.

II. Notice of Proposed Rulemaking

    The notice of proposed rulemaking (NPRM) for an amendment to the 
starter interlock requirement of Federal Motor Vehicle Safety Standard 
(FMVSS) 571.102 was published on May 15, 2003 (68 FR 26269). We 
intended the proposed amendment to preserve the original safety intent 
of the starter interlock requirement while accommodating the 
technologies used on vehicles such as the Prius and the Insight. With 
respect to vehicles with automatic transmissions, the agency proposed 
regulatory text that made it clear that, after activation of the 
vehicle's propulsion system by the driver, the internal combustion 
engine (ICE) is permitted to stop and start automatically while the 
shift position is in any forward drive gear. The agency also proposed 
regulatory text providing that the ICE is permitted to stop and start 
automatically while the shift position is in Reverse, but only in 
vehicles like the Prius that exhibit creep force in forward and reverse 
drive gears, regardless of whether the ICE is running. This allows the 
driver to sense what gear the vehicle is in before pressing the 
accelerator pedal. This creep force is similar to the creep force that 
exists on conventional (non-hybrid-electric) ICE/automatic transmission 
equipped vehicles. Creep force occurs in the direction indicated by the 
selected shift position and provides enough force to cause motion of a 
vehicle loaded to its GVWR on a level, paved surface before the service 
brake pedal is completely released. In the NPRM, we stated that creep 
force is a cue that indicates to the driver that he or she is in the 
correct gear, as the driver is releasing the brake and has the best 
chance of stopping quickly in case of a gear selection error. In the 
NPRM, we also proposed a test for minimum creep force in vehicles that 
automatically stopped and started its ICE in Reverse.
    For a complete discussion of the safety issues that led to proposed 
changes to FMVSS No. 102, and how NHTSA sought to address these issues, 
please refer to the notice of proposed rulemaking at 68 FR 26269 (May 
15, 2003).
    The comment period for the NPRM ended on July 15, 2003.

III. Public Comments to the NPRM

    We received comments from ten sources; Advocates for Highway and 
Auto Safety (AHAS), American Honda Motor Company (Honda), Ford Motor 
Company (Ford), Nissan North America, Inc. (Nissan), Association of 
International Automobile Manufacturers, Inc. (AIAM), International 
Truck and Engine Corporation (International), DaimlerChrysler 
Corporation (DaimlerChrysler), New York City Transit (NYCT), Toyota 
Motor North America, Inc. (Toyota), and Denso International America, 
Inc. (Denso). The commenters included a consumer advocate, vehicle 
manufacturers, vehicle manufacturer associations, a city transportation 
department and manufacturers of controls used in hybrid-electric 
vehicles.
    In general, the comments supported amending FMVSS No. 102 to 
clarify its requirements and facilitate current and evolving hybrid 
electric vehicle technologies. However, specific commenters raised a 
variety of issues

[[Page 38042]]

relating to creep force and the conditions under which creep force 
should be present. The issues raised in the public comments, and 
NHTSA's response to the comments, are discussed below.

IV. Public Comments and NHTSA's Response

A. Requiring Reverse Creep Force in Vehicles That Allow the ICE To Stop 
and Start Automatically When the Vehicle's Shift Position Is in Reverse

    Both AHAS and AIAM indicated support for NHTSA's proposal to 
require reverse creep force in vehicles that allow the ICE to stop and 
start automatically while the vehicle's shift position is in Reverse. 
AHAS commended the agency for anticipating a safety problem before it 
reaches a level where increasing deaths and injuries have been 
sustained by both vehicle occupants and pedestrians.
    Ford and NYCT supported NHTSA's efforts to revise the Federal Motor 
Vehicle Safety Standards (FMVSS) for starter interlock function in 
order to address the new hybrid-electric vehicle (HEV) propulsion 
systems. They indicated concern, however, that the proposed rule 
appears to assume that creep force will help drivers avoid collisions 
resulting from shifting errors. Ford and NYCT stated there are no 
historical or experimental data provided in support of such a 
proposition. Ford further argued that the new specification requiring a 
creep force was inserted without any analysis or documentation of the 
real-world benefit. Ford indicated that vehicles equipped with manual 
transmissions do not have creep force while standing at idle and that 
several non-HEV models equipped with automatic transmissions actually 
have reduced or eliminated idle creep force (for fuel economy purposes) 
by partially disengaging the transmission or reducing engine speed at 
idle. Ford further argued that by imposing a minimum creep force 
requirement on HEVs, NHTSA arbitrarily would hold HEVs to a higher 
standard than many conventional power trains with automatic 
transmissions and all power trains with manual transmissions. Ford 
stated that NHTSA has presented no evidence that a vehicle without 
creep force is less safe than one with creep force.
    Toyota commented that it understands that the agency's purpose in 
measuring and regulating a creep force to GVWR ratio is to develop a 
method to measure driver observable movement; however, it believes 
there are other ways to alert the driver that his or her vehicle is in 
Reverse, such as an audible alarm. Toyota believes that an audible 
alarm should be allowed as a substitute for reverse creep force.
    In response to the comments from AHAS and AIMA, NHTSA notes that it 
sought to amend S3.1.3 of FMVSS No. 102 in a way that allows for 
current and new technology and at the same time does not compromise the 
original safety intent of FMVSS No. 102.
    NHTSA acknowledges the comments from Ford and NYCT regarding creep 
force. Even though NHTSA continues to consider creep force a valuable 
cue to the driver, it has concluded that the changes necessary to 
accommodate these and other comments discussed in this document would 
make the regulatory language unnecessarily complex. Therefore, NHTSA 
has developed a refocused approach to differentiate between two types 
of hybrid-electric vehicles: the electric motor-powered vehicle 
assisted by an internal combustion engine (ICE) (such as the Prius) and 
the ICE-powered vehicle assisted by an electric motor and that employs 
idle-stop technology (such as the Insight).
    This final rule establishes requirements that address the same 
objectives of solving the mis-shift problem before it happens but in a 
way such that we no longer need to regulate creep force. The changes in 
this final rule clarify how the starter interlock requirement applies 
to vehicles with emerging technologies while continuing to address the 
need for safety. We believe the restriction of idle-stop systems to 
forward gears is simple and appropriate. We have also lessened 
restrictions on electric motor-powered vehicles assisted by an ICE, 
thereby maximizing design freedom where appropriate.

B. Applicability to Vehicles Over 10,000 Pounds GVWR

    International, a U.S. manufacturer of medium and heavy-duty trucks, 
school buses and medium duty diesel engines recommended that the 
proposed changes to the regulation be limited to internal combustion 
(IC)/electric hybrid vehicles with GVWRs less than 10,000 pounds so the 
regulation does not inhibit the development of new technology or create 
an unworkable situation for medium and heavy duty vehicles.
    International commented that NHTSA has collected data on light duty 
hybrid (IC)/electric passenger vehicles, even though the proposed 
changes would apply to all vehicles. International expressed concern 
that the proposed changes may not be appropriate for medium and heavy-
duty vehicles and there is not enough information or data available at 
this time on medium and heavy-duty hybrid-electric vehicles (HEVs). 
International stated that development of HEVs with GVWRs greater than 
10,000 pounds has not progressed to the same degree as light duty 
passenger vehicles. Since HEVs with GVWRs greater than 10,000 pounds 
have many uses, they have different operating characteristics than 
lighter HEVs, presenting challenges not addressed by the proposed 
changes. International also expressed concern that there do not appear 
to be data addressing whether the proposed creep force requirements are 
appropriate for vehicles with GVWRs greater than 10,000 lbs. 
International further stated that NHTSA should also be aware that in 
addition to IC/electric hybrid vehicles, research is ongoing for IC/
hydraulic hybrid medium duty vehicles. Since the proposed changes have 
been specifically written for IC/electric hybrid vehicles, applying 
these proposed changes to other types of hybrids could pose problems.
    NYCT expressed concern that the proposed rule fails to allow for 
different configurations possible with electric, hybrid-electric, and 
fuel cell vehicles. NYCT commented that the proposed rule appears to be 
based on the characteristics of two parallel hybrid-electric gasoline 
ICE passenger cars (Toyota Prius and Honda Insight) currently in large-
scale production. In addition, NYCT indicated that the survey data 
provided on creep force in Table 1 of the NPRM (at 68 FR 26274) is 
limited to passenger cars and light trucks of less than 18,000 lbs. 
GVWR.
    NYCT stated that on conventional ICE vehicles with automatic 
transmissions, creep force provides an anti-rollback function, an 
important safety feature, on moderate grades. However, the heavy-duty 
series hybrid-electric buses currently operated by NYCT have an anti-
rollback system without creep force. The propulsion system 
automatically provides torque to prevent rolling backward when the 
brakes are released on an ascending grade (and also to prevent rolling 
forward when the bus is in reverse on a descending grade). However, 
this feature does not allow the vehicle to move in the selected 
direction until the accelerator is depressed. NYCT has found this 
arrangement effective for preventing rollback. However, the proposed 
rule appears to prohibit this design since the rule requires creep 
force. NYCT stated that the proposed rule would require NYCT's vehicle 
suppliers to re-design part of their

[[Page 38043]]

propulsion systems. The attendant engineering costs could have a very 
significant impact on vehicle lifecycle costs for NYCT, particularly 
since the North American market for heavy-duty hybrid-electric transit 
buses is currently limited to a few hundred units per year.
    In response, NHTSA recognizes the comments from International and 
NYCT on heavier hybrid vehicles. We realize the NPRM's creep force 
requirement may conflict with some systems currently used on heavy 
trucks and buses. In fact, series systems used on some buses, where the 
ICE is strictly used to generate electrical power and is not connected 
to the vehicle drive train, would have been prohibited from stopping in 
Reverse when it was not needed. This would have caused additional 
changes and exceptions to the proposed language in the NPRM, leading to 
additional complexity. The issues presented by International and NYCT 
are solved by new language in this final rule. The new requirements do 
not create problems for larger vehicles with series hybrid systems and 
anti-rollback systems and does not affect the development of new 
technologies.

C. Specifying a Maximum Throttle Opening Regardless of Driver Throttle 
Input on Idle-Stop Systems During Automatic ICE Starting

    In the NPRM, we asked for comment on whether we should require a 
limit on throttle opening on idle-stop systems when the engine is 
automatically starting. The limit on throttle opening would prevent 
vehicle surging when the driver may rapidly remove his foot from the 
brake and depress the accelerator to full throttle just before or as 
the engine automatically starts. Although such vehicle surging is not a 
problem on the Prius and Insight, it was suggested that such a 
requirement might be necessary for future idle-stop designs.
    Comments from AHAS supported the idea that vehicles that allow the 
ICE to stop and start automatically should not cause sudden 
acceleration of the vehicle even when the accelerator pedal is fully 
depressed during ICE automatic starting.
    Honda did not agree with new criteria which would limit throttle 
opening. Honda agrees with NHTSA that it is necessary to design the 
idle-stop system to prevent sudden surging during normal operation and 
during failure modes; however, Honda believes that additional criteria 
may inhibit future idle-stop development. Honda commented that in its 
system, when the accelerator pedal is pushed quickly and aggressively 
after the brake pedal is released, the Honda Integrated Motor Assist 
(IMA) is capable of restarting the ICE quickly. The first engine firing 
occurs after the brake pedal is released and before the accelerator 
pedal is depressed. After the brake pedal is released, brake pressure 
is maintained while the transmission automatically and rapidly shifts 
to neutral during engine restarting. After the engine has started, the 
transmission rapidly shifts to Drive and brake pressure is released. 
The drive train is engaged quickly and electrically controlled to 
prevent surging engine revolutions and to prevent vehicle surging. 
Therefore, on the Insight, Honda said it is unnecessary to place 
additional limits on the throttle. If the engine should fail to start 
when the brake is released, brake pressure is maintained and the 
transmission is in Neutral. The starter turns the engine but is limited 
to a 2 second duration. Honda indicated that there are many ways in 
addition to controlling the throttle opening, to control the engine 
revolutions and prevent vehicle surging. Such additional ways include 
retarding the ignition fire timing and cutting the fuel injection. In 
the future, idle-stop technology may be applied to vehicles that use 
Drive By Wire (DBW) systems where throttle opening is easily controlled 
electronically. However, requiring control of the throttle opening now 
could mandate specific hardware, such as DBW, which could inhibit other 
types of advanced technologies.
    Nissan agreed it is necessary to consider the unexpected movement 
of a stopped vehicle in the design process, but opposed a specified 
maximum throttle position as a means to achieve design goals. Nissan 
commented that design specific regulations could restrict development 
of alternative technologies to meet the same goal. For example, another 
possible method to control unexpected movement during an automatic 
engine start is to limit the output of the transmission to the drive 
axles. While the ability of such a system may be equal to or better 
than the use of an artificial maximum throttle position, it would not 
be an acceptable alternative if throttle position is regulated. To 
allow for the broadest range of technologies, Nissan suggested the 
agency regulate the threshold and response of the vehicle to the given 
condition, and allow each manufacturer to decide how best to achieve 
the desired performance.
    AIAM supported the need for safeguards to prevent sudden surging of 
the vehicle when the engine automatically starts.
    International indicated that there might be situations in which 
limiting power might prevent the operator from avoiding a crash. If the 
vehicle is stopped on railroad tracks or in the middle of an 
intersection, the ability to rapidly accelerate might allow the 
operator to avoid a crash. International recommended that the maximum 
allowable acceleration or jerk of the vehicle during an engine start be 
limited to the same value as the acceleration or jerk with the engine 
already running. This limitation would prevent sudden motions that the 
operator is not used to but would allow full power to be available for 
emergency maneuvers.
    DaimlerChrysler commented that it was in favor of limiting the 
throttle opening to less than or equal to \1/4\ throttle.
    Toyota commented that in addition to NHTSA's concerns, the 
situation may arise where a regulation limiting maximum throttle could 
hinder a driver from escaping a situation in which the driver may have 
intentionally wanted full throttle. Considering both sides of the 
issue, Toyota recommended that the agency allow manufacturers to 
continue developing and incorporating their own means to balance 
throttle control.
    NHTSA notes that a requirement to regulate throttle opening during 
automatic engine start emerged out of concerns that in future systems, 
vehicle surging may result when drivers of vehicles equipped with idle-
stop systems go from braking to full throttle very quickly, before or 
while the ICE was in the process of automatically starting. The Honda 
Insight handles this scenario well, as when the accelerator is fully 
depressed during automatic engine start, the engine starts and the 
vehicle gradually accelerates without surging or any unexpected 
movement. Such a scenario is of no consequence to the Toyota Prius, as 
actuation of the accelerator to any degree, at any time, will initiate 
vehicle movement exactly like a conventional non-hybrid-electric 
vehicle with an automatic transmission, as the electric motor will move 
the vehicle during situations where the engine is stopped or in the 
process of automatically starting.
    The majority of the comments were in favor of preventing possible 
vehicle surging in idle-stop systems by allowing manufacturers to 
continue to design safeguards of their choosing into their systems. The 
comments indicate that a requirement limiting throttle opening could 
possibly limit the use of other techniques and designs that would also 
prevent vehicle surging when the ICE automatically starts during full 
throttle. Comments also indicated that limiting full throttle might 
place a driver/vehicle in a dangerous position in cases where full 
throttle is needed. NHTSA knows that vehicle surging is not an issue 
for

[[Page 38044]]

the Prius or the Insight. NHTSA agrees with comments that anticipated 
safety issues can be solved by a variety of well-designed approaches. 
NHTSA concludes that since current systems have addressed this issue 
and the requirement to limit throttle opening may inhibit other methods 
and techniques to prevent surging in vehicles with idle-stop systems, 
no action should be taken on this issue at this time.

D. Requiring a Manual Override To Deactivate the Idle-Stop Feature

    In the NPRM, we requested comment on whether FMVSS No. 102 should 
include a requirement for a manual idle-stop override, to allow the 
driver to disable the idle-stop system and prevent the engine from 
automatically stopping in cases such as an idle-stop system malfunction 
or a delay in automatic starting.
    Honda did not agree with NHTSA's proposal, which would require a 
control that permits the driver to manually deactivate or override the 
idle-stop system. Honda indicated that it has incorporated a number of 
fail-safe features in its Integrated Motor Assist system that 
automatically prevents the idle-stop system from operating due to such 
conditions as low battery power, cold engine, or brake switch failure. 
Honda did not think a manual lockout function is needed because it 
could create unnecessary confusion and opportunities for misuse. Honda 
believes it is the manufacturer's responsibility to design systems to 
perform properly under all driving conditions and to be convenient and 
fail-safe by using automatic techniques that are appropriate for the 
technology employed. Honda stated that regulating specific features, 
such as a manual lockout, is not necessary at this time and could 
restrict some future technologies.
    Nissan agreed that the idle-stop system should cease to function in 
the event of a system malfunction; however, Nissan and the AIAM opposed 
a requirement for a control that would allow the operator to lock out 
or turn off the system. Given that an idle-stop system (one that 
includes diagnostic functions) can automatically cease its function and 
provide equivalent safety performance without operator control, Nissan 
does not believe that an external control is necessary for all systems. 
Additionally, if the system provides a control that would allow the 
operator to lock out or turn off the system, the improvement in fuel 
economy, the main purpose of the idle-stop, could be reduced. Nissan 
concluded that a control allowing the operator to deactivate the system 
is not needed if the system includes a diagnostic function. AIAM 
provided similar reasons for their opposition to a manual control for 
locking out an idle-stop system.
    International commented that the engine controller should detect if 
the system is degrading, then shut down the idle-stop system and 
provide a ``service engine'' type message. Some fleets and owners/
operators prefer to avoid new controls because of added distraction and 
such a control would rarely be used, which means the operator may 
forget its location or proper use. Such controls would allow truck and 
bus drivers to lockout the system based on personal preference, even 
though it is operating properly, thus eliminating many of the benefits 
of the system.
    DaimlerChrysler indicated that it would expect a manual override to 
be permitted and not just for malfunctions. In the override mode, the 
transmission and engine control system would meet the current FMVSS No. 
102 requirements. One minute would seem like a reasonable time in 
``auto stop'' mode before an ``auto start'' should occur. This could 
accommodate most traffic signal stops or pauses in traffic. 
DaimlerChrysler also commented it assumes that manual, as well as, 
automatic overrides of this engine control strategy would be permitted. 
For example, during high and low ambient temperature conditions, it may 
be advantageous to automatically override the ``auto stop'' feature to 
permit use of air conditioning, defroster, electrically heated seats, 
or to recharge a discharged battery.
    Toyota's comments expressed concerns that requiring an idle-stop 
override would allow consumers to disable the idle-stop system and 
negate its environmental benefits. Toyota stressed that manufacturers 
already design their own safeguards to address malfunctions or 
excessive automatic starting times. Different manufacturers may use 
different strategies and regulating this area, at this time, may 
inhibit introduction of new technologies. In order to advance the 
introduction of idle-stop technology, Toyota stated its belief that the 
agency should continue to allow manufacturers to design in their own 
algorithms to address these concerns. For example, Toyota's algorithms 
ensure the vehicle continues to be operational if there is a problem 
with the hybrid system. In Toyota's designs, the vehicle reverts to an 
``engine on'' mode, during which the vehicle's engine remains on until 
the ignition is turned off, similar to current conventional internal 
combustion engine vehicles.
    In response, NHTSA notes that it raised the issue of a manual 
override in the NPRM as there were concerns that as vehicles equipped 
with idle-stop systems age, a delay in ICE restarting may develop. 
NHTSA anticipates that the idle-stop feature will eventually become 
commonplace on a significant number of conventional non-hybrid 
vehicles. Delays in vehicle restarting, as well as inoperable vehicles 
due to malfunctioning idle-stop systems is a potential future safety 
concern. NHTSA cannot predict the design of these future systems nor 
the automatic overrides they may include. A manual override requirement 
would provide a measure of safety until such automatic overrides and 
their performance tests/criteria could be defined. The majority of 
commenters did not agree that an idle-stop system manual override was 
necessary. However, comments did indicate that automatic overrides may 
be important. Honda has addressed the issue of overriding the idle-stop 
system in its design of the Insight by preventing the engine from 
automatically stopping during certain malfunctions with the idle-stop 
system or during conditions when the idle-stop system would not perform 
well. Therefore, as a result of these public comments, NHTSA will not 
include a requirement for a manual override in this final rule. NHTSA 
will monitor the performance of idle-stop systems as they develop and 
take action as necessary.

E. Maximum Time Between Brake Pedal Release and Propulsion System 
Availability

    In the NPRM, we sought comments on whether there should be a limit 
on the time it takes for an ICE to start automatically once the brake 
pedal reaches the fully released position. We were concerned that as 
idle-stop systems age, the time interval between brake pedal release 
and automatic engine start may become excessive. Delays in engine 
restarting may have safety implications in situations where vehicles 
are stopped at intersections or railroad crossings and must accelerate 
quickly to avoid other traffic or emergency vehicles.
    Nissan commented that the time required for the propulsion system 
to be available to move the vehicle after the brake pedal is released 
may be different depending on the circumstances and on multiple design 
and performance target factors. For example, starting the vehicle after 
a traffic signal changes to green, making a right turn through an 
intersection, turning left through an

[[Page 38045]]

intersection in front of an oncoming vehicle, accelerating or merging 
into traffic, and moving slowly through congested traffic, may all 
require different availability and response times from the propulsion 
system. Nissan indicated that it would decide the allowable time for 
such a propulsion system to be available to move the vehicle after the 
brake pedal is released based on an analysis of safety and performance 
factors and the expected consumer acceptance of the system. Nissan 
indicated that the agency should not restrict design choices, but 
rather should allow manufacturers the flexibility to decide the 
allowable time for its vehicles.
    International recommended that the interval should be no longer 
than the time it takes the operator to move his foot from the brake to 
the accelerator. When a driver applies the accelerator, his expectation 
is that the vehicle will accelerate and any delay has the potential to 
cause confusion or problems. International stated it is likely that the 
time between brake pedal release and availability of the propulsion 
system would be a customer acceptance issue and need not be regulated.
    NHTSA notes that although commenters thought that the maximum 
permitted time between brake pedal release and propulsion system 
availability should be a consideration during design of idle-stop 
systems, commenters did not favor including a minimum time requirement 
in the final rule. Commenters stated their belief that this issue was 
one of customer acceptance and should be left up to manufacturers. 
NHTSA acknowledges that such delays are not an issue with the Prius and 
the Insight and the anticipation of such a problem presents no more 
risk than a non-HEV that develops a hesitation problem during 
acceleration. Therefore, NHTSA will not amend the regulatory text to 
include a minimum time requirement for ICE automatic starting.

F. Leaving FMVSS No. 102 Unchanged and Placing New Requirements in a 
Separate Standard

    International recommended that FMVSS No. 102 remain as is and that 
a new standard be added that would apply to hybrid-electric vehicles. 
International stated its belief that trying to incorporate hybrid-
electric vehicles within FMVSS No. 102 is ``very confusing'' and the 
confusion will be compounded as other types of hybrid vehicles are 
developed in the future.
    While NHTSA has considered this comment, it has decided not to 
place the requirements for hybrid-electric vehicle propulsion systems 
in a separate standard at this time. In the NPRM, exceptions were 
simply added to existing starter interlock requirements for vehicles to 
clarify that ICEs may automatically stop and start after driver 
activation. NHTSA believes that the FMVSS No. 102 language in this 
final rule is straightforward and easy to understand as written. In the 
future, if further regulation of hybrid/hybrid-electric vehicle 
propulsion systems becomes necessary and if such regulation should 
become complex and confusing, NHTSA may then consider efforts to 
separate and further clarify requirements.

G. Use of the Term ``Driver Activation''

    DaimlerChrysler commented that the current state-of-the-art and 
research are still evolving and the term ``Driver Activation'' in the 
Executive Summary (at 68 FR 26270) of the NPRM is not clearly defined. 
The hybrid-electric vehicles mentioned in the NPRM provide the driver 
with an alternate means of starting the engine without using the 
ignition key. DaimlerChrysler recommended that we clarify whether 
starting the engine without using the ignition key falls under the 
Automatic Activation heading. At the same time DaimlerChrysler believes 
the safety purposes of FMVSS No. 102 should be preserved.
    In response, ``driver activation'' as used by the agency in this 
rulemaking, relates to the current state-of-the-art. ``Driver 
activation'' distinguishes between the driver's initial turning on of 
the propulsion system (which may include the starting of the vehicle's 
ICE) versus the propulsion system's automatic stopping and starting of 
the ICE, which occurs only after the driver's initial activation. 
Whatever action it takes for the driver to initially activate the 
vehicle's propulsion system and place the vehicle in a mode where its 
propulsion system can operate and move the vehicle is considered 
``driver activation.'' Driver activation includes such actions as 
inserting a key into the ignition and turning it, pushing a starter 
button, and activating a remote keyless starting system.
    In the NPRM, the term ``after the driver has activated the 
vehicle's propulsion system'' was used because in hybrid-electric 
vehicles such as the Toyota Prius, if certain conditions are met (such 
as the engine is warm, and the batteries are charged), when the driver 
turns the ignition on and attempts to start the ICE, the ICE may not 
start because it may not be needed. Even if the ICE is not needed and 
doesn't start, the driver is still enabling the propulsion system and 
when the shift position is placed in a drive gear, the electric motor 
will provide creep force, as well as power the vehicle when the 
accelerator is depressed. After the driver has activated the vehicle's 
propulsion system, the ICE may automatically start and stop as needed. 
NHTSA believes that the wording used in the Executive Summary and the 
proposed regulatory text accurately describes driver activation and 
automatic engine starting in hybrid-electric vehicles.

H. ``Shift Position'' Versus ``Shift Lever Position''

    Toyota commented that in the NPRM and in FMVSS 102, the terms 
``position of the lever'' and ``shift position'' are used 
interchangeably. Toyota believes the more appropriate term is ``shift 
position''. Toyota made this comment because advanced technologies have 
resulted in vehicles with computerized transmissions and electronic 
shifters such as joysticks. The ``position of the lever'' for such 
systems does not always correspond to the ``shift position''. 
Therefore, Toyota recommends that the agency ensure the term ``shift 
position'' is used in place of the term ``position of the lever.''
    In response, NHTSA agrees with the comment from Toyota. When FMVSS 
No. 102 was initially written, all transmissions were controlled by 
mechanically linked shift levers that sequenced serially from one 
position to the next. If the lever was positioned next to the letter D, 
the driver knew that the vehicle was in a forward drive gear. Neutral 
had to be located between Reverse and Drive so that the system would 
transition through Neutral when changing back and forth between Drive 
and Reverse. Presently, shift-by-wire technology and electronically 
controlled transmissions have led to joystick-type shifters where the 
shifter returns to a resting position after a gear is selected. If the 
shifter is momentarily pushed to the D position, the transmission 
shifts to Drive, a Drive telltale light illuminates to let the driver 
know the transmission is in Drive and the shifter, when released, 
returns to its rest position. The telltale light, not the shifter 
position, tells the driver what gear the transmission is in. In such a 
system, when shifting from Drive to Reverse, the transmission 
automatically transitions from Drive to Neutral to Reverse.
    Such systems are not limited to joysticks. In some systems push 
buttons and paddle shifters are also used. In all of these cases, the 
telltale light, not the position of the lever, paddle, or button,

[[Page 38046]]

tells the driver of the transmission gear. Whether a paddle, lever or 
button is used for shifting, the transmission must automatically 
transition through Neutral when going back and forth between Drive and 
Reverse. Recently, NHTSA issued an interpretation to Lemf''rder 
Corporation (August 1, 2002) which submitted diagrams of several 
joystick sequences. The interpretation evaluated these sequences and 
discussed whether or not they were in compliance with the sequence 
requirements of FMVSS No. 102. NHTSA believes that in view of present 
and emerging shift selection technology, it would be more accurate if 
the amended portions of FMVSS No. 102 addressed ``shift position'' 
rather than ``shift lever position.'' The title of FMVSS No. 102 is 
also amended to read: ``Transmission shift position sequence, starter 
interlock, and transmission braking effect.'' Portions of the standard 
that specifically refer to systems with shift levers (S3.1.1.1) will 
remain as written.

I. Clarification of When the ICE May Stop and Start

    Comments from Denso requested clarification of exclusions for the 
starter interlock requirements as they appear in the regulatory text of 
the NPRM. Denso indicated that NHTSA's NPRM prescribes conditions under 
which a vehicle engine may stop and restart automatically when the 
transmission shift lever is in a forward or reverse drive position, as 
exclusions to the general starter interlock requirements (S 4.1.3 of 
the NPRM). Denso stated its belief that the proposed amendment means 
that the exclusions permit the engine to ``stop and restart'' 
automatically when the transmission shift lever is kept in a forward 
position (without shifting the lever from the forward position to a 
reverse position) in S4.1.3.1, or while the lever is kept in a reverse 
position (without shifting the lever from the reverse position to a 
forward position) in S4.1.3.2.
    However, Denso stated that in actual driving conditions and 
depending on system design, the shift lever need not always be in the 
same position when the engine stops and restarts. For example, the 
engine may automatically stop when the transmission shift lever is in a 
forward position and then automatically restart after the lever has 
been shifted from the forward position to a reverse position. 
Similarly, the engine may automatically stop when the transmission 
shift lever is in a reverse position and then automatically restart 
after the lever has been shifted from the reverse position to a forward 
position. Denso commented that in the latter two cases, it is not clear 
that either S4.1.3.1 or S4.1.3.2 should be applied. Denso further 
stated that it is not clear whether the engine in the two cases is 
permitted to automatically restart. Therefore, Denso requested that 
NHTSA review the exclusions to S4.1.3 to clarify its application, 
considering all transmission shift lever positions.
    Denso also commented that S4.1.3.2 of the NPRM would require 
vehicles having an automatic engine stop/start feature that operates 
when the vehicle is in reverse gear to meet creep force requirements 
whenever the transmission shift lever is in a reverse position and 
requires manufacturers to demonstrate compliance with the creep force 
requirements by testing the vehicle with the engine stopped. Denso 
submitted a Table ``Examples of Engine/Motor Operation flow when the 
Transmission Shift Lever is in a Reverse Position'' (the Table) which 
provides examples of possible automatic engine and motor operation flow 
\3\ for hybrid-electric vehicles (HEVs) and internal combustion engine 
only vehicles (ICEVs). Denso indicated that the operational status of 
the engine and the motor when the transmission shift lever is shifted 
to the reverse position and when the brake pedal is partially/fully 
released are classified into ``motor operation only'', ``engine 
operation only'', and ``simultaneous motor and engine operation''. 
Denso commented that it is not clear how the proposed rule would be 
applied to the scenarios, which are shown in the Table and asked NHTSA 
to clarify how the proposed rule will apply to each case. The Table 
appears in Denso's comments in DOT Docket No. NHTSA-2003-14907-9.
---------------------------------------------------------------------------

    \3\ Operational status of the engine and the motor having an 
automatic engine stop and restart function, at each phase, from the 
time the vehicle is stationary with the brake pedal fully applied, 
through the time the acceleration pedal is applied.
---------------------------------------------------------------------------

    Denso also asked that regarding the creep force compliance test, 
according to the Table, the systems that operate by automatically 
restarting the engine on and before the brake pedal is fully released 
(scenarios numbers 6 to 8, 11, 12, Nos.13 to 18, Nos. 20 to 22 in the 
Table) cannot be tested to justify the compliance with the creep force 
requirement; because it appears that these systems cannot achieve the 
engine stopped condition specified in S4.1.3.2. Denso wanted advice as 
to what test procedures would apply to these cases. Denso stated its 
belief that NHTSA's intent for requiring the creep force is to warn 
driver of what gear the vehicle is engaged in and asked NHTSA to state 
the rule more clearly and to address the cases listed in the Table. 
Moreover, Denso urged NHTSA not to unnecessarily restrict future 
developments of stop/start technologies.
    In response, NHTSA notes that the new language in this final rule 
states that after the driver has activated the vehicle's propulsion 
system, the engine may stop and restart automatically when the 
transmission shift position is in any forward drive gear. When the 
transmission shift position is in reverse gear, this final rule permits 
the engine to restart automatically if two conditions are satisfied. 
Both conditions apply to the situation where the engine is 
automatically stopped in a forward drive shift position and the driver 
selects Reverse. The first condition is that the engine must restart 
immediately when the service brake is applied. The second condition is 
that the engine does not start automatically if the service brake is 
not applied. The final rule also provides that the engine may stop and 
start anytime after the driver has activated the vehicle's propulsion 
system if the vehicle's propulsion system can propel the vehicle in the 
normal travel mode in all forward and reverse drive gears without the 
engine operating and if the engine automatically starts while the 
vehicle is traveling at a steady speed and a steady accelerator control 
setting, the engine does not cause the vehicle to accelerate.
    The final rule language permits a vehicle like the Insight to 
automatically stop and start the engine in forward gears; however, when 
the driver selects Reverse, the engine must start and remain running in 
Reverse. The final rule language also permits vehicles like the Prius 
to allow its engine to automatically start and stop anytime after 
driver activation of the propulsion system. The Prius engine may stop 
in a forward gear and restart in Reverse or may stop while in Reverse 
and restart in a forward gear.
    Denso asked us to clarify how the proposed rule would apply to each 
of the scenarios in the Table. Each scenario describes the status of 
the ICE, electric motor, brake pedal and accelerator while the shift 
position is in Reverse. Denso also asked that we comment and/or clarify 
how scenarios numbers 6,7,8,11,12,13,14,15,16,17,18,20,21,22 would be 
tested using the test procedure described in S5 of the NPRM.
    The new language that appears in this final rule does not use creep 
force to distinguish between types of hybrid vehicles and does not 
include a test for minimum creep force. Therefore, any concerns about 
how certain scenarios would be tested for minimum creep force are now 
moot.

[[Page 38047]]

J. Other Issues Raised in Response to the NPRM

    The following five issues were also raised in response to the NPRM.
    1. Minimum Creep Force Value of 1.5 Percent of GVWR--
DaimlerChrysler commented that the creep force ratio defined as .015 
(creep force/GVWR) is a good starting point. Ford commented that there 
is not enough data to support the specific minimum value of creep force 
proposed. NYCT expressed concern about the proposal to require a creep 
force of at least 1.5 percent of GVWR, as Table 1 of the NPRM did not 
include data from any commercial vehicles.
    2. Applicability of the Phrase ``Brake Pedal Released'' to Air 
Brakes--International commented that air brake systems have different 
operating characteristics than do hydraulic brake systems. Statements 
in S4.1.3.2 of the NPRM such as ``before the brake pedal is released'' 
and ``with the brake pedal released'' have a different interpretation 
when addressing a vehicle with hydraulic versus air brakes. 
International also stated that S5.1.7 needs more detail. International 
asked if the system passes if the device registers in the last .001 
inch of pedal movement. International stated that a better test may 
define this in terms of creep force being present at certain points in 
the pedal travel or at pedal forces less than a certain value.
    3. Requiring Creep Force in Reverse When the ICE Is Both ``On'' and 
``Off''--International commented that the creep force requirement in 
reverse gear should apply if the engine is on or off. If a vehicle sits 
in Reverse for a long time, the engine may start up to recharge the 
battery or to run the heating and air conditioning systems. Confusion 
may occur if the driver assumes the vehicle is in a forward gear 
because the engine is running. Therefore International recommends 
removing the reference to the state of the combustion engine in the 
definition of Creep Force (S3) and rewriting S5.1.7 to include testing 
with the engine off and with the engine on.
    4. Use of the Term ``Electric Motor'' in the Regulatory Text--
International indicated that references to an electric motor in the 
definition of ``creep force'' (S3) of the NPRM exclude future 
technologies and will require a change to the regulation with each new 
technology introduced.
    5. Use of the Term ``Battery'' in the Regulatory Text--
International commented that the reference to the word ``battery'' in 
S5.1.2 of the NPRM should differentiate between the starter battery and 
the propulsion battery (propulsion energy storage system). A 95 percent 
charge for the starter battery is satisfactory. A suggested state of 
charge for the propulsion battery is its nominal low limit.
    NHTSA notes that these five issues were raised in response to NPRM 
language that proposed to specify and regulate creep force. This final 
rule removes the use of creep force to distinguish between the two 
types of hybrid-electric vehicles and removes the performance test for 
creep force. New language makes the same distinction between the same 
vehicles with substantially similar language, but in a simpler manner. 
The new language creates no problems for vehicles equipped with air 
brakes. In view of the new language that appears in this final rule, 
the five series of comments addressing creep force issues are no longer 
applicable.

V. Final Rule

    In the NPRM, we proposed to limit the operation of idle-stop 
systems to forward gears in order to minimize the possibility of 
vehicle crashes resulting from shifting errors. In an idle-stop 
equipped vehicle, if the engine is stopped and the driver has 
mistakenly placed the vehicle in Reverse, there is no cue from creep 
force and the shifting error may not be realized until the accelerator 
pedal is pressed and the engine automatically restarts. When the driver 
presses the accelerator, he may be surprised when the vehicle 
accelerates rearward rather than forward. Such situations can cause 
property damage, as well as, injuries and deaths to pedestrians. 
Allowing idle-stop systems to operate only in forward gears has fewer 
ramifications, as the driver will learn to associate automatic engine 
stopping and starting with forward motion.
    However, amending Standard 102 to prohibit all vehicles, including 
hybrid-electric vehicles, from automatically stopping and starting the 
engine in Reverse would have no safety purpose for a vehicle like the 
Prius in which engine starting has no effect on its low speed 
operation. Therefore, a distinction should be made between the two 
types of hybrid vehicles. In the NPRM, the agency attempted to 
distinguish between these two types of hybrid-electric vehicles 
(electric motor-powered vehicle assisted by an ICE (such as the Prius) 
vs. the ICE-powered vehicle assisted by an electric motor (such as the 
Insight)) by requiring vehicles that allow its ICE to automatically 
stop and start in Reverse to exhibit creep force in Reverse when the 
engine is stopped. The Insight does not stop the engine in Reverse and 
if the engine is automatically stopped in a forward gear, it starts 
immediately when Reverse is selected and the service brake is applied. 
The Prius exhibits creep force in reverse with its ICE stopped and 
therefore, the requirement permitted both hybrid vehicle designs while 
limiting the operation of idle-stop systems for conventional vehicles 
to forward gears only.
    Public comments to the NPRM questioned the validity of specifying 
creep force, raising questions as to conditions under which creep force 
should be exhibited, and how the proposed amendment would apply to 
series hybrid-electric systems.\4\ Because solutions to the issues 
raised by public comments would increase the complexity of the 
regulatory language, we began to consider alternatives that would meet 
the same objectives that we sought in the NPRM.
---------------------------------------------------------------------------

    \4\ The series system discussed is one where vehicle motive 
power is obtained strictly from electric motors connected to the 
drive train and the sole purpose of the ICE is to rotate a generator 
that supplies electrical power to charge batteries and supply 
electrical power to drive motors.
---------------------------------------------------------------------------

    A refined, simpler approach was developed and appears in this final 
rule. This approach makes the same distinction between vehicles as does 
the NPRM and produces a substantially similar outcome. This final rule 
generally requires that the engine starter be inoperative when the 
transmission shift position is in a forward or reverse drive position. 
However, after the driver has activated the vehicle propulsion system, 
the engine may stop and start automatically when the transmission shift 
position is in any forward drive gear. The rule prohibits the engine 
from automatically stopping in reverse gear. When the engine is 
automatically stopped in a forward drive shift position and the driver 
selects Reverse, this final rule permits the engine to restart 
automatically in Reverse if two conditions are satisfied. The first 
condition is that the engine must restart immediately whenever the 
service brake is applied. The second condition is that the engine does 
not start automatically if the service brake is not applied.
    A second exception applies to vehicles like the Prius where 
unrestricted engine starting introduces no safety issues. The final 
rule specifies that the engine may automatically stop and start anytime 
after the driver has activated the vehicle's propulsion system if the 
vehicle's propulsion system can propel the vehicle in its normal travel 
mode in all forward and reverse drive gears without the engine 
operating, and if the engine

[[Page 38048]]

automatically starts while the vehicle is traveling at a steady speed 
and a steady accelerator control setting, the engine does not cause the 
vehicle to accelerate. This new wording makes a distinction between two 
types of hybrid vehicles (Insight and Prius) as does the NPRM. The 
final rule permits the idle-stop feature to operate in forward gears 
for any vehicle but prohibits it from functioning in Reverse unless the 
vehicle has special characteristics that are specified in simple 
language. If the engine on an idle-stop equipped vehicle is stopped in 
a forward gear and the shift position is changed to Reverse, it 
requires the brake to be depressed before the engine starts. Therefore, 
if Reverse is selected by mistake, the driver's foot is on the brake 
and he or she is prepared to stop the vehicle. It also allows for 
vehicles like the Prius, which behaves like a conventional ICE/
automatic transmission equipped vehicle no matter what the status of 
the ICE. Therefore, this different approach that appears in this final 
rule makes the same distinction between the same vehicles as does the 
NPRM and achieves an outcome substantially similar to that in the NPRM 
but in a simpler manner. The approach in the final rule permits the 
designs of the Insight and the Prius for which the original 
interpretations were written. The final rule also permits the designs 
used on the hybrid-electric Civic, Accord and the redesigned Prius, as 
well as series hybrid-electric systems used in heavy vehicles such as 
buses. The final rule imposes no burden on manufacturers of current 
hybrid vehicles, and allows for flexibility in future designs. Finally, 
this final rule does not compromise the original safety intent of 
Standard 102.

VI. Statutory Bases for the Final Rule

    We have issued this final rule pursuant to our statutory authority. 
Under 49 U.S.C. Chapter 301, Motor Vehicle Safety (49 U.S.C. 30101 et 
seq.), the Secretary of Transportation is responsible for prescribing 
motor vehicle safety standards that are practicable, meet the need for 
motor vehicle safety, and are stated in objective terms. 49 U.S.C. 
30111(a). When prescribing such standards, the Secretary must consider 
all relevant, available motor vehicle safety information. 49 U.S.C. 
30111(b). The Secretary must also consider whether a proposed standard 
is reasonable, practicable, and appropriate for the type of motor 
vehicle or motor vehicle equipment for which it is prescribed and the 
extent to which the standard will further the statutory purpose of 
reducing traffic accidents and deaths and injuries resulting from 
traffic accidents. Id. Responsibility for promulgation of Federal motor 
vehicle safety standards was subsequently delegated to NHTSA. 49 U.S.C. 
105 and 322; delegation of authority at 49 CFR 1.50.
    As a Federal agency, before promulgating changes to a Federal motor 
vehicle safety standard, NHTSA also has a statutory responsibility to 
follow the informal rulemaking procedures mandated in the 
Administrative Procedure Act at 5 U.S.C. Section 553. Among these 
requirements are Federal Register publication of a general notice of 
proposed rulemaking, and giving interested persons an opportunity to 
participate in the rulemaking through submission of written data, views 
or arguments. After consideration of the public comments, we must 
incorporate into the rules adopted, a concise general statement of the 
rule's basis and purpose.
    The agency has carefully considered these statutory requirements in 
promulgating this final rule to amend FMVSS No. 102. As previously 
discussed in detail, we have solicited public comment in an NPRM and 
have carefully considered the public comments before issuing this final 
rule. As a result, we believe that this final rule reflects 
consideration of all relevant available motor vehicle safety 
information. Consideration of all these statutory factors has resulted 
in the following decisions in this final rule.
    In the NPRM, we proposed to limit the operation of idle-stop 
systems to forward gears in order to minimize the possibility of 
vehicle crashes resulting from shifting errors. In an idle-stop 
equipped vehicle, if the engine is stopped and the driver has 
mistakenly placed the vehicle in Reverse, there is no cue from creep 
force and the shifting error may not be realized until the accelerator 
pedal is pressed and the engine automatically restarts. When the driver 
presses the accelerator, he may be surprised when the vehicle 
accelerates rearward rather than forward. Such situations can cause 
property damage, as well as, injuries and deaths to pedestrians. 
Allowing idle-stop systems to operate only in forward gears has fewer 
ramifications, as the driver will learn to associate automatic engine 
stopping and starting with forward motion.
    However, amending Standard 102 to prohibit all vehicles, including 
hybrid-electric vehicles, from automatically stopping and starting the 
engine in Reverse would have no safety purpose for a vehicle like the 
Prius in which engine starting has no effect on its low speed 
operation. Therefore, we decided to make a distinction between the two 
types of hybrid vehicles. In the NPRM, the agency attempted to 
distinguish between these two types of hybrid-electric vehicles (idle-
stop/Insight and the Prius) by requiring vehicles that allow its ICE to 
automatically stop and start in Reverse to exhibit creep force in 
Reverse when the engine is stopped. The Insight does not stop the 
engine in Reverse and if the engine is automatically stopped in a 
forward gear, it starts immediately when Reverse is selected and the 
service brake is applied. The Prius exhibits creep force in reverse 
with its ICE stopped and therefore, the requirement permitted both 
hybrid vehicle designs while limiting the operation of idle-stop 
systems for conventional vehicles to forward gears only.
    Public comments to the NPRM questioned the validity of specifying 
creep force, raising questions as to conditions under which