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Interpretation ID: nht88-1.66

TYPE: INTERPRETATION-NHTSA

DATE: 03/07/88

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: ASSOCIATE ADMINISTRATOR FOR RESEARCH & DEVELOPMENT

TITLE: ACTION: ACCEPTABILITY OF ADVANCED BRAKE LIGHT DEVICE AS AN AFTERMARKET UNIT

ATTACHMT: ATTACHED TO LETTER DATED 04/01/88 EST, TO CARL KALPAN, FROM MICHAEL M. FINKELSTEIN, REDBOOK A33, STANDARD 108; LETTER DATED 11/30/81 TO KENNETH G MOYER FROM FRANK BERNDT; LETTER DATED 05/02/84 TO LAWRENCE F. HENNEBERGER FROM FRANK BERNDT

TEXT: This is in reply to your memorandum of February 19, 1988, with respect to an advanced brake light device developed by ATAT Technology of Israel. You have described the device as one which activates "the stoplamps of a vehicle upon release of the acceler ator and before actual application of the service brake". You attached a draft of a letter to ATAT for our comment, and you have asked for our opinion of the acceptability of the device for aftermarket installation.

We have made minor changes to the draft. As you know, Standard No. 108 contains no requirements directly applicable to vehicles in use, and the sole prohibition of the Vehicle Safety Act directed to vehicles in use is that no manufacturer, dealer, or v ehicle repair business may render inoperative, in whole or in part, any device or element of design installed in accordance with a safety standard. As the device in question appears to involve the wiring of lighting equipment, it does not appear to be a modification of a nature easily done by a vehicle owner.

The threshold question for the aftermarket is, does a modification of this nature render inoperative in whole or in part a device or element of design installed in accordance with Standard No. 108. We equate "in accordance with" to mean "necessary for c ompliance with". From your description, we know only one thing about the device: the stoplamps are activated upon release of the accelerator, or conversely, the stoplamps are activated by means other than application of the service brakes.

Both Standard No. 108 and agency interpretations indicate that the device would create a noncompliance with Standard No. 108, and hence be unacceptable as either original or aftermarket equipment. Paragraph S4.5.4 of Standard No. 108 states:

"The stoplamps on each vehicle shall be activated upon application of the service brakes. The high-mounted stoplamp on each passenger car shall be activated only upon application of the service brakes."

We assume that all stoplamps on new passenger cars are wired to activate simultaneously. Because activation of the center lamp may only be accomplished by activation of the service brakes, and the Israeli device would activate the lamp without brake app lication, its use would create a noncompliance with Standard No. 108. Although the first sentence of S4.5.4 in contrast with the second does not expressly prohibit application of the lower mounted stoplamps by means other than brake application, the age ncy has taken the position that all stoplamps on a vehicle must be activated simultaneously (Letter of Oct. 21, 1985 to Kenneth Deane opining that a 35 millisecond delay would be considered "simultaneous"). This means that the vehicle could not be wired so that the lower mounted stoplamps would activate upon release of the accelerator but the center lamp would not. For vehicles equipped with the center high-mounted stop lamp, the Israeli device would create a noncompliance with new vehicle requirement s, and, for the aftermarket, result in a wiring and use of lamps noncompliant with new vehicle requirements, hence rendering that system partially ineffective within the meaning of the statute.

With respect to aftermarket installation on vehicles not equipped with center high-mounted lamps, different considerations obtain. In 1981 Kenneth Moyer wrote us about an "alert device which automatically turns on the stop lamps of the vehicle when the accelerator is released". We responded on November 30, 1981, citing paragraph 2.1 of SAE Standard J586d, Stop Lamps, which defines the lamp as one whose operation indicates "the intention of the operator of a vehicle to stop or diminish speed by braking ". Because Mr. Moyer's device would activate the stop lamp under a condition indicating an intent other than the above, we informed him that his device would create an "impairment" and a lack of effectivity as well, and that it would be prohibited. I a ttach a copy of this letter for your information, as it appears directly on point with the ATAT system, and because some of the agency's comments about the inventor's assumptions appear to remain relevant.

In contrast is the agency's opinion regarding use of the Jacobs brake retarder system, in which the stoplamps are activated when the retarder is in use (see letter of May 2, 1984, to Lawrence Henneberger). The manufacturer argued that use of the stoplam ps when the retarder was activated would indicate "that the vehicle is diminishing its speed by braking...." In Mr. Henneberger's view two 1974 agency interpretations allowing combination of retarder controls with foundation brake controls impliedly requ ire activation of the stoplamps when supplementary braking devices are used. The agency agreed with both these arguments.

I hope that this information is useful to you.

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