Interpretation ID: nht79-2.44

DATE: 03/27/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: L. B. Leiby

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of February 7, 1979, to the Department asking about the legality of wiring the rear hazard warning signals so that they automatically flash when the gear shift lever is placed in reverse.

We are able to give you guidance about applicable Federal law only. The Federal requirements for new motor vehicles are set forth in Federal Motor Vehicle Safety Standard No. 108 (49 Code of Federal Regulations 571.108). As you probably know, the hazard warning system and the turn signal system typically use the same lights. There is no provision in the standard which prohibits a manufacturer from wiring the rear hazard signals/turn lights so that they flash when the vehicle gear shift is in reverse. Please note, however, that the standard (S4.6(b)) requires the separate rear tail lamps to be steady burning. Thus, those lamps may not be wired so that they flash.

As for modification of used vehicles, contact the State in which the modified vehicle would be licensed and operated to determine if it has any applicable vehicle-in-use laws.

We appreciate your interest in motor vehicle safety.

SINCERELY,

7 February 1979

Dear Sir,

I am working on a concept which if legal and feasible, will, I believe, reduce accidents in parking areas.

The concept concerns the utilization of blinker lights normally used for highway emergency purposes to be wired to the backup lights circuit so that when the gear shift lever is placed in reverse, the red tail lights will automatically blink thus providing extra warning to oncoming drivers in parking areas.

Can you provide information as to the legality of the above concept, and please include any related factors.

Thank you.

Lawrence B. Leiby