Federal Motor Vehicle Safety Standards; Stability and Control of Medium and Heavy Vehicles During Braking

DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. 92-29; Notice 11]

RIN 2127-AG06

Federal Motor Vehicle Safety Standards; Stability and Control of

Medium and Heavy Vehicles During Braking

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

ACTION: Final rule.

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SUMMARY: This document amends Standard No. 121, Air Brake Systems, to

specify the location, labeling, color, activation protocol, and

photometric intensity of antilock brake system (ABS) malfunction

indicator lamps on the exterior of trailers and trailer converter

dollies. The purpose of the malfunction indicator lamp is to inform

drivers, and maintenance and inspection personnel, of malfunctions in a

trailer's ABS.

DATES: Effective dates. The amendments to 49 CFR 571.121 are effective

March 1, 1997.

Compliance dates. Compliance with the amendments to paragraph

S5.2.3.3 (b) will be required on and after March 1, 1998.

Incorporation by reference. The incorporation by reference of a

publication listed in the regulation is approved by the Director of the

Federal Register as of March 1, 1997.

Petitions for reconsideration. Any petitions for reconsideration of

this rule must be received by NHTSA no later than November 7, 1996.

[[Page 49692]]

ADDRESSES: Petitions for reconsideration of this rule should refer to

the above referenced docket numbers and should be submitted to:

Administrator, National Highway Traffic Safety Administration, 400

Seventh Street, S.W., Washington, D.C. 20590.

FOR FURTHER INFORMATION CONTACT: For non-legal issues: Mr. Robert M.

Clarke, Office of Crash Avoidance, National Highway Traffic Safety

Administration, 400 Seventh Street, SW., Washington, D.C. 20590 (202)

366-5278.

For legal issues: Mr. Marvin L. Shaw, NCC-20, Rulemaking Division,

Office of Chief Counsel, National Highway Traffic Safety

Administration, 400 Seventh Street, SW., Washington, D.C. 20590 (202)

366-2992.

SUPPLEMENTARY INFORMATION:

I. Background

II. Petitions for Reconsideration and Notice of Proposed Rulemaking

III. Comments on the December NPRM

IV. Agency Decision

A. General Considerations

B. Location

C. Color

D. Activation Protocol

E. Intensity and Photometric Requirements

V. Costs

VI. Rulemaking Analyses and Notices

I. Background

On March 10, 1995, NHTSA published a final rule amending Federal

Motor Vehicle Safety Standard (FMVSS) No. 121, Air brake systems, to

require medium and heavy vehicles to be equipped with an antilock brake

system (ABS) (60 FR 13216). Truck tractors will be required to be

equipped with ABS beginning March 1, 1997, and air-braked trailers and

single-unit trucks will be required to be so equipped beginning March

1, 1998. These vehicles also will be required to be equipped with

indicator lamps to alert their drivers of ABS malfunctions. Each truck

equipped to tow trailers, including a truck tractor, will be required

to be equipped with two in-cab warning lamps: one to indicate

malfunctions of its own ABS, and another to indicate ABS malfunctions

on units it tows. Trailers will be required to be equipped with an

electrical circuit capable of signaling a trailer ABS malfunction to

the cab of the towing unit.

NHTSA recognized that, during the initial transition period, there

is a high likelihood that new ABS-equipped trailers will frequently be

towed by older, non ABS-equipped tractors or trucks that will not have

the capability to receive ABS malfunction signals transmitted from

trailers. Accordingly, to provide drivers, and maintenance and

inspection personnel, with the ability to determine a malfunction with

the trailer ABS, the agency has required that trailers (including

converter dollies) also be required to be equipped with a separate

external ABS malfunction indicator. The March 10, 1995, final rule

specified an interim eight-year period, from March 1, 1998, to March 1,

2006, during which these external ABS malfunction indicator lamps must

be installed on trailers.1 The agency reasoned that, after that

time period, there would be sufficient new ABS-equipped truck tractors

and towing trucks fitted with in-cab trailer ABS malfunction warning

indicators to obviate the need for the separate trailer-mounted ABS

malfunction warning lamp. The agency intended the trailer-mounted lamps

to be visible to drivers using their outside rearview mirrors.

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1 A final rule responding to petitions for

reconsideration extended this requirement until March 1, 2009 (61 FR

5949, February 15, 1996).

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II. Petitions for Reconsideration and Notice of Proposed Rulemaking

NHTSA received 16 petitions for reconsideration to the March 10,

1995 final rule. Most of these petitions addressed testing and

implementation issues associated with the requirements for ABS. In

addition, Midland-Grau and the Truck Trailer Manufacturers Association

(TTMA) requested changes in the requirements for external trailer ABS

malfunction indicator lamps. Specifically, they petitioned NHTSA to

delete the requirement that the external malfunction indicator lamp on

a trailer be visible from the driver's seating position ``through the

rearview mirrors.'' (see S5.2.3.3). Midland-Grau stated that since

truck tractor manufacturers cannot control where the external lamp

would be located, requiring tractor manufacturers to ensure that the

lamp is visible from the cab of the truck tractor is unreasonable. TTMA

stated that since trailer manufacturers cannot control where mirrors

are located on tractors, requiring the ABS malfunction lamp on dollies

and trailers to be visible ``through the rearview mirrors'' is not

appropriate. That organization also stated that there is no good,

practical location for such a lamp on a dolly.

On December 13, 1995, NHTSA published two notices in response to

the petitions for reconsideration: (1) A final rule (60 FR 63965) that

amended portions of the standard dealing with ABS and stopping distance

requirements, and (2) a notice of proposed rulemaking (NPRM) (60 FR

64010) that proposed changing the requirements for the location, color,

and intensity of the external ABS malfunction lamps on trailers and

dollies.

On February 15, 1996, NHTSA issued another final rule (61 FR 5949)

that responded to 13 petitions for reconsideration to the December 13,

1995 final rule. Specifically, the agency amended the trailer ABS

electrical powering requirements and adopted a four-year delay in the

effective date on which truck tractors and trucks equipped to tow

trailers must be capable of receiving and displaying ABS malfunction

warning signals from trailers. Because of the delay in the requirement

for in-cab signaling, the agency extended the transition period during

which trailers must be equipped with the external ABS malfunction

indicator. Thus, these lamps must be equipped on trailers manufactured

on and after March 1, 1998, and before March 1, 2009.

III. Comments on the December NPRM

NHTSA received comments on the proposal to amend the external

trailer ABS malfunction indicator requirements from TTMA, Midland-Grau,

the American Trucking Associations (ATA), the American Society of

Safety Engineers (ASSE), Truck-Lite, Inc., and Grote Industries, Inc.

The commenters generally agreed with the need for the external trailer

ABS malfunction indicator lamp. Most commenters requested that the lamp

be located at the trailer's rear rather than at its front. The agency's

responses to specific comments about the lamp's location, labeling,

color, activation protocol, and photometric requirements are set forth

below.

IV. Agency Decision

A. General Considerations

After reviewing the comments and other available information, NHTSA

has decided to adopt requirements with respect to the location, color,

activation protocol, and photometric intensity of the external ABS

malfunction lamps on trailers and trailer converter dollies. The ABS

malfunction indicator lamp on a trailer will have to be mounted near

the rear of the left side of the trailer, no closer than 150 mm (5.9

inches) and not more than 600 mm (23.6 inches) from the rear red side

marker lamp. The ABS malfunction indicator lamp for a converter dolly

will have to be mounted on a permanent structure on the dolly at least

375 mm (14 inches) above the road surface. In all cases, the

malfunction indicator lamp must be yellow and be illuminated whenever

power is supplied to the ABS and there

[[Page 49693]]

is a malfunction. The lamps will also meet the requirements for

combination clearance side marker lamps specified by the Society of

Automotive Engineer's (SAE's) Recommended Practice J592 July 1972 or

JUN92 which is referenced in Standard No. 108. The specific details of

each requirement are discussed below

B. Location

In the December 1995 NPRM, NHTSA proposed that the trailer ABS

malfunction indicator lamp be located on the left side of each trailer,

as close to the front as practicable, and at a height as close as

practicable to 96 inches above the road surface. The proposed location

requirement was patterned after a previous agency proposal to require a

low air pressure warning lamp on trailers. (55 FR 4453, February 8,

1990) The proposed height was consistent with the mean driver eye

height, as reported in a University of Michigan study.2 Given

anticipated practicability problems for some trailers, such as flatbeds

and lowboys, the agency also proposed that the malfunction indicator

lamp could be located on the front of the trailer, as far leftward as

possible and at a height as close to 96 inches as practicable.

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\2\ ``The Influence of Truck Driver Eye Position on the

Effectiveness of Retroreflective Traffic Signs,'' by Sivak,

Flannagan, and Gellatly, September 1991.

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Truck-Lite agreed with the proposal to locate the external ABS

indicator near the front of the trailer. TTMA, ATA, Midland-Grau, and

Grote recommended that this indicator be located at the rear of the

trailer near the red side marker lamp. They stated that such a location

would allow the indicator to be visible and readily detected when

activated, provided that the ABS malfunction indicator were yellow.

These commenters stated that such a location would be readily visible

to drivers who use the red side marker lamp as a visual location cue to

help them track the lateral position of their trailer when making

turns.

NHTSA has decided to require that the external trailer ABS

malfunction indicator lamp be located near the rear of the trailer. The

agency believes that this lamp will be readily seen by drivers using

their rearview mirrors, and during walkaround vehicle inspections. The

agency notes that this lamp will only activate in those rare situations

when the trailer ABS has malfunctioned. The external trailer ABS

malfunction indicator must be located near the rear of the left side of

a trailer when viewed from the rear of the trailer, no closer than 150

mm (5.9 inches) and not more than 600 mm (23.6 inches) from the rear

red side marker lamp. The agency selected this range to ensure a

standardized location of this lamp near the trailer rear, thereby

facilitating its being viewed by drivers, while providing flexibility

to trailer manufacturers. This requirement combines the suggestions of

Midland-Grau, TTMA, ATA, and Grote, concerning the specific location

requirements for the trailer ABS malfunction indicator relative to the

red rear side marker lamp.

This decision reflects several considerations. In this standardized

location, the lamp can be seen by drivers, as well as fleet maintenance

and roadside inspection personnel, during pre-trip and post-trip

inspections. Platform trailers, pole/logging trailers, and other

miscellaneous trailers typically lack a front face. Based on Table 1

below, these trailers account for approximately 25 percent of all

trailers. For such trailers, a front mounting position of the external

malfunction indicator would have been problematic. In contrast, an

external malfunction indicator can be mounted on the rear left of all

trailers, even platform and other trailers that may have had difficulty

complying with the proposal for locating the indicator by the trailer's

front face. Moreover, locating the lamp in the rear also reduces

installation costs and improves durability since less wire will be

needed between the ABS electronic control unit (ECU) and the light it

activates, compared to locating the indicator at the front of trailers.

Accordingly, NHTSA believes that requiring the indicator lamp to be

located on the rear left side will provide manufacturers sufficient

latitude and flexibility in equipping their trailers with this lamp.

Table 1.--U.S. Commercial Truck Fleet by Major Body Type * (1992)

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Percent of

Cargo body type 1992 fleet

population

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Platform................................................... 22.2

Van........................................................ 44.5

Auto Transport............................................. 1.5

Dump....................................................... 10.1

Grain Bodies............................................... 4.2

Garbage/Refuse............................................. 0.4

Livestock.................................................. 1.3

Pole/Logging............................................... 3.2

Tank/Dry Bulk.............................................. 2.0

Tank/Liquids or Gas........................................ 7.4

Others..................................................... 3.2

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Total................................................ 100.0

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* Source: 1992 Truck Inventory and Use Survey, U.S. Census Bureau.

Truck-Lite was the only commenter to specifically address NHTSA's

proposal to require that a malfunction indicator lamp be placed on a

permanent structure of the dolly and be visible to a person standing on

the road surface near the location of the indicator. That commenter

agreed with the agency's proposal. Since the agency continues to

believe that the proposed location for dollies is appropriate, the

agency has decided to adopt the location requirement for dollies, as

proposed.

C. Color

In the December 1995 NPRM, NHTSA proposed that the external ABS

malfunction indicator be yellow. The agency reasoned that this color

was consistent with the requirements in Standard No. 101, Controls and

displays, which requires that in-vehicle ABS malfunction indicator

lamps be yellow. The agency further stated that selecting this color

would harmonize the requirement with the vehicle standards of the

International Organization for Standardization (ISO) and the Economic

Commission for Europe (ECE) which specify red to indicate brake failure

and yellow to indicate ABS malfunction. While NHTSA recognized that

these color requirements are applicable to instrument panel lamps and

do not address ABS malfunction indicator lamps on the exterior of a

vehicle, the agency stated that it is desirable to have a uniform

protocol. The agency tentatively concluded that the same requirements

should be applied to external ABS malfunction lamps since they perform

the same function as in-vehicle ABS malfunction lamps. The agency

further concluded that a green status lamp on the trailer exterior

would be inconsistent with the already established convention, thereby

creating confusion among drivers.

TTMA, Midland-Grau, and Grote recommended that the external ABS

malfunction indicator lamp be yellow, provided that it was located at

the trailer's rear. These commenters believed a yellow color was

necessary to make it possible for drivers to distinguish this lamp from

the red rear side marker lamp. They stated that a yellow lamp would be

visible and readily detected, when activated, because the red rear side

marker lamp is now routinely seen by drivers using their rearview

mirrors. ATA stated, without explanation, that a yellow malfunction

indicator should not be mounted at the trailer's rear. ATA favored a

green status indicator, stating that the SAE Truck and Bus ABS Task

Force had recently issued a

[[Page 49694]]

recommended practice that ``status indicators'' on a vehicle's exterior

should be green and should illuminate when the ABS is operating

properly.

After reviewing the available information, NHTSA has decided to

require the external trailer ABS malfunction indicator lamp to be

yellow. The agency believes that yellow will minimize confusion, be

readily understandable by drivers, and be distinguishable from the red

rear side marker lamps.3 NHTSA believes that while a green light

is appropriate to indicate that a system is operating properly, it

would be potentially confusing to indicate that a system such as the

trailer ABS is malfunctioning. The commonly accepted convention for

indicating the readiness of a system is an activated green light. NHTSA

notes that there would be no prohibition against supplementing the

required yellow external malfunction indicator lamp on a trailer with a

green lamp on the ECU to indicate the trailer ABS's status. Such a

supplemental lamp would not have to conform to any of the color or

protocol requirements specified for the external trailer ABS

malfunction indicator lamp.

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\3\ Table I of Standard 108 includes a requirement for, on the

side of each trailer, a yellow clearance lamp at the front and a red

clearance lamp at the rear.

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TTMA, ATA, Midland-Grau, and Grote suggested that the trailer ABS

malfunction indicator lamp be labeled with the letters ``ABS'' to

distinguish this lamp from other, otherwise identical, yellow side

marker lamps. They suggested several ways to distinguish the yellow

side markers from the trailer ABS indicator, including a decal on the

lens itself; a permanent marking on the lens or its housing; or a

permanent decal or plaque affixed to the trailer structure, at a

location immediately adjacent to the lamp.

NHTSA has decided to require the yellow trailer ABS malfunction

indicator lamp to be identified with the letters ``ABS'' to distinguish

this lamp from the yellow side marker/clearance lamps. This

identification is intended to inform drivers and others making a pre-

trip inspection that this lamp functions as a trailer ABS malfunction

indicator. The agency has specified several acceptable methods of

permanently marking the lamp to provide manufacturers with flexibility

in complying with this requirement. Specifically, a manufacturer may

use any of the following ways to permanently identify the trailer ABS

malfunction indicator: marking the lens, marking the lens housing,

affixing a label or plaque to the trailer near the indicator, or

painting the trailer near the indicator.

NHTSA is also specifying minimum character size requirements for

the indicator lamp identification, which are based on generally

recognized human factors design principles.4 The agency based its

selection of the character sizes on its assumption that 15 feet was a

reasonable estimate of the distance between the driver or mechanic

during a pre-trip walk-around inspection of a trailer.

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\4\ ``Visual Display Character Size,'' Woodson, WE Human Factor

Design Handbook, McGraw-Hill, New York, 1981, pages 494-495.

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D. Activation Protocol

In earlier comments and its petition for reconsideration, TTMA

requested the lamp to be lit continuously when the ABS is functioning

properly and to be extinguished when there is a malfunction in the ABS.

NHTSA addressed this issue in detail in the March 1995 final rule

on heavy vehicle ABS rulemaking. In that notice, the agency decided to

require that the ABS malfunction indicator lamp be lit when a

malfunction exists and not be lit when the antilock system is

functioning properly. S5.2.3.3 of Standard No. 121 further requires

that the trailer ABS malfunction indicator lamp be lit during the

check-of-lamp function only when the vehicle is stationary and power is

first supplied to the antilock system. This allows the ABS lamp on a

trailer that is moving to undergo the check of lamp function, without

the lamp cycling on and off whenever the brakes are applied. The agency

stated that such a requirement eliminates distractions for the driver

and for drivers of adjacent vehicles, created by the ABS lamp cycling

on and off with every brake application. The agency emphasized that in

the event of a malfunction in the trailer antilock system, the

malfunction indicator lamp would be lit whenever power is supplied to

the trailer antilock system, regardless of whether the vehicle is

stationary or moving. Accordingly, the agency decided to deny TTMA's

request in its petition for a change in the ABS malfunction indicator

lamp protocol and proposed no change to the protocol included in the

ABS final rule.

No commenter addressed the trailer ABS indicator's activation

protocol.

NHTSA continues to believe that the ABS malfunction indicator lamp

should follow the accepted convention of activating when a malfunction

exists and not activating when the antilock system is functioning

properly. Thus, this protocol, first contained in the March 10, 1995

final rule requirements, remains in effect.

E. Intensity and Photometric Requirements

In their original petition to the March 10, 1995 final rule, AAMA

and TTMA petitioned NHTSA to require that the external ABS malfunction

indicator lamp be subject to the same photometric 5 requirements

as those specified in Standard No. 108.

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5 Photometric values specify the amount of light emitted

by a lamp, when measured from a specified distance.

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NHTSA tentatively agreed with these petitioners in its December 13,

1995, final rule and proposed that the lamps meet the photometric

requirements for clearance, side marker, and identification lamps

specified by SAE Recommended Practice J592 JUN92 for clearance lamps,

which are referenced in Standard No. 108. Specifically, the agency

proposed that ABS malfunction indicator lamps meet the photometric

performance requirements specified in SAE J592 JUN92 for the luminous

intensity of side marker lamps. Those requirements specify minimum

intensity values at test points of 45 degrees along a horizontal axis

and 10 degrees along a vertical axis, when measured from a lamp

distance of at least three meters. In addition, the agency proposed

that the lamp be mounted on the trailer in such a manner that its beam

is directed toward the front of the trailer and rotated 90 degrees so

that its top and bottom become its sides. The agency believed that such

an orientation of the lamp would ensure that its widest light beam is

in a vertical plane just outboard of the side of the trailer, and hence

would be more likely to be visible by the driver through the tractor's

rearview mirrors.

Truck-Lite, TTMA, and Midland-Grau requested that conformance be

allowed to the July 1972 version of SAE J592 (as well as the June 1992

version), since that earlier version is referenced in Standard No. 108

and many currently manufactured and stocked lamps have been certified

as having met that version of the standard. These commenters also

stated that the agency's proposal to rotate the lamp 90 degrees was

inappropriate since the requirement would necessitate designing new

lamps for an extremely limited market. They suggested that such a

redesign would add costs for little apparent gain. Alternatively, they

requested the agency require the use of a combination clearance/side

marker lamp instead of a

[[Page 49695]]

simple side marker lamp, because the combination lamps, which have

``PC'' or ``P2'' marked on the lens or housing in accordance with SAE

J579c, Lighting Identification Code, have a uniform and wide diffused

beam pattern throughout the full 180 degree left and right range. Thus,

if this type lamp was used, rotating the lenses, or mounting the lamp

facing toward the front of the trailer would be unnecessary.

After reviewing the comments, NHTSA has amended the standard to

permit conformance to either the July 1972, or June 1992 version of SAE

J592. Additionally, the standard has been amended to require that a

combination clearance/side marker lamp with a ``PC'' or ``P2'' marked

on the lens or housing in accordance with SEA J759 Jan 95, Lighting

Identification Code, be used as the external trailer ABS warning lamp.

The agency agrees with the commenters that this change will provide

additional flexibility, without any detriment to safety. Based on the

available information concerning the light output pattern of

combination clearance/side marker lamps, the agency has decided that

rotating lamps is not necessary to achieve the intended function of

this lamp.

V. Costs

NHTSA has already evaluated the economic impact of requiring

trailers and dollies to be equipped with an external ABS malfunction

indicator lamp in the final rule on heavy vehicle ABS published on

March 10, 1995. The agency estimated that the unit cost of requiring an

ABS lamp on trailers and dollies is $9.43. Since this rule does not

require additional equipment, but only specifies location, color and

photometric intensity for the trailer ABS malfunction indicator lamp,

the rule should not have any impact on previously estimated costs or

benefits. The agency notes that there will be some nominal additional

costs associated with the labeling requirements. There will also be

some cost savings, compared to the December 1995 proposal, since

manufacturers will not have to redesign those trailers lacking a front

face on which to install a malfunction indicator lamp. Under the

proposal, a significant minority of trailers (approximately 25 percent)

would have needed a permanent structure attached to the trailer to

comply with the proposed requirement. Locating the lamp in the rear

also reduces installation costs and improves durability since less wire

will be needed between the ABS electronic control unit (ECU) and the

light it activates, compared to locating the indicator at the front of

trailers.

VI. Rulemaking Analyses and Notices

1. Executive Order 12866 (Federal Regulatory Planning and Review) and

DOT Regulatory Policies and Procedures

This rulemaking was not reviewed under E.O. 12866. NHTSA has

analyzed this proposal and determined that it is not ``significant''

within the meaning of the Department of Transportation's regulatory

policies and procedures. The impacts of the rule are so minimal as not

to warrant preparation of a full regulation evaluation. As noted above,

NHTSA has already evaluated the economic impact of requiring an

external ABS malfunction indicator lamp. For details, see the Final

Economic Assessment (FEA) titled, ``Final Rules FMVSS Nos. 105 & 121

Stability and Control While Braking Requirements and Reinstatement of

Stopping Distance Requirements for Medium and Heavy Vehicles,''

published in June 1994.

2. Regulatory Flexibility Act

In accordance with the Regulatory Flexibility Act, NHTSA has

evaluated the effects of this action on small entities. Based upon this

evaluation, I certify that the amendment will not have a significant

economic impact on a substantial number of small entities. Vehicle and

brake manufacturers typically do not qualify as small entities.

Further, aside from the relatively small cost impacts noted above, the

amendment will not affect costs or benefits beyond those addressed in

the (FEA) for the ABS final rule. Accordingly, no regulatory

flexibility analysis has been prepared.

3. Executive Order 12612 (Federalism)

This action has been analyzed in accordance with the principles and

criteria contained in Executive Order 12612, and it has been determined

that the rule does not have sufficient Federalism implications to

warrant preparation of a Federalism Assessment. No State laws are

affected.

4. National Environmental Policy Act

The agency has considered the environmental implications of this

rule in accordance with the National Environmental Policy Act of 1969

and determined that the rule does not significantly affect the human

environment.

5. Civil Justice Reform

The rule does not have any retroactive effect. Under section 103(d)

of the National Traffic and Motor Vehicle Safety Act (49 U.S.C. 30111),

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.

Section 105 of the Act (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 suit in court.

List of Subjects in 49 CFR Part 571

Imports, Incorporation by reference, Motor vehicle safety, Motor

vehicles, Rubber.

In consideration of the foregoing, the agency is amending Standard

No. 121, Air Brake Systems, in Title 49 of the Code of Federal

Regulations, Part 571 as follows:

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS

1. The authority citation for Part 571 continues 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 571.121, as revised at 61 FR 27290 effective March 1,

1997, is amended by revising S5.2.3.3, to read as follows:

Sec. 571.121 Standard No. 121; Air brake systems.

* * * * *

S5.2.3.3 Antilock malfunction indicator.

(a) In addition to the requirements of S5.2.3.2, each trailer and

trailer converter dolly manufactured on or after March 1, 1998, and

before March 1, 2009, shall be equipped with an external antilock

malfunction indicator lamp that meets the requirements of S5.2.3.3 (b)

through (d).

(b)(1) The lamp shall be designed to conform to the performance

requirements of Society of Automotive Engineers (SAE) Recommended

Practice J592 JUN92, or J592e, July 1972, Clearance, Side Marker, and

Identification Lamps, for combination, clearance, and side marker

lamps, which are marked with a ``PC'' or ``P2'' on the lens or housing,

in accordance with SAE J759 Jan 95, Lighting Identification Code. SAE

J592 June 92, SAE J592e July 1972, and SAE J759 January 1995, are

incorporated by reference and thereby are made part of this standard.

The Director of the Federal Register approved the material

[[Page 49696]]

incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR

part 51. Copies of the material may be inspected at NHTSA's Docket

Section, 400 Seventh Street, SW., room 5109, Washington, DC, or at the

Office of the Federal Register, 800 North Capitol Street, NW.,

Washington, DC.

(2) The color of the lamp shall be yellow.

(3) The letters ``ABS'' shall be permanently molded, stamped, or

otherwise marked or labeled in letters not less than 10 mm (0.4 inches)

high on the lamp lens or its housing to identify the function of the

lamp. Alternatively, the letters ``ABS'' may be painted on the trailer

body or dolly or a plaque with the letters ``ABS'' may be affixed to

the trailer body or converter dolly; the letters ``ABS'' shall be not

less than 25 mm (1 inch) high. A portion of one of the letters in the

alternative identification shall be not more than 150 mm (5.9 inches)

from the edge of the lamp lens.

( c) Location requirements. (1) Each trailer that is not a trailer

converter dolly shall be equipped with a lamp mounted on a permanent

structure on the left side of the trailer as viewed from the rear, no

closer than 150 mm (5.9 inches), and no farther than 600 mm (23.6

inches), from the red rear side marker lamp.

(2) Each trailer converter dolly shall be equipped with a lamp

mounted on a permanent structure of the dolly so that the lamp is not

less than 375 mm (14.8 inches) above the road surface when measured

from the center of the lamp with the dolly at curb weight. When a

person, standing 3 meters (9.8 feet) from the lamp, views the lamp from

a perspective perpendicular to the vehicle's centerline, no portion of

the lamp shall be obscured by any structure on the dolly.

(d) The lamp shall be illuminated whenever power is supplied to the

antilock brake system and there is a malfunction that affects the

generation or transmission of response or control signals in the

trailer's antilock brake system. The lamp shall remain illuminated as

long as such a malfunction exists and power is supplied to the antilock

brake system. Each message about the existence of such a malfunction

shall be stored in the antilock brake system whenever power is no

longer supplied to the system. The lamp shall be automatically

reactivated when power is again supplied to the trailer's antilock

brake system. The lamp shall also be activated as a check of lamp

function whenever power is first supplied to the antilock brake system

and the vehicle is stationary. The lamp shall be deactivated at the end

of the check of lamp function, unless there is a malfunction or a

message about a malfunction that existed when power was last supplied

to the antilock brake system.

* * * * * *

Issued on: September 11, 1996.

Ricardo Martinez,

Administrator.

[FR Doc. 96-23796 Filed 9-20-96; 8:45 am]

BILLING CODE 4910-59-P