Interpretation ID: nht90-3.67

TYPE: Interpretation-NHTSA

DATE: August 27, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Carol Zeitlow -- Manager, Engineering Services, Oshkosh Truck Corporation

TITLE: None

ATTACHMT: Letter dated 8-1-90 to T. Vincon from C. Zeitlow; (OCC 5067); also attached to photocopies of Federal Register (text omitted)

TEXT:

This in reply to your letter of August 1, 1990, to Taylor Vinson of this Office, with respect to Motor Vehicle Safety Standard No. 108.

You ask for confirmation that "the hazard warning light should always over-ride the stop lamp" when they are "together on a vehicle." I am pleased to provide that confirmation. Under the relevant SAE materials on stop lamps that are incorporated by ref erence in Standard No. 108, when a stop signal is optically combined with the turn signal, the circuit shall be such that the stop signal cannot be turned on if the turn signal is flashing. Because the hazard warning system operates through the turn sig nal lamps, the stop signal cannot be turned on in an optically combined lamp if the hazard system is in use.

You have also noted that in your version of Standard No. 108, no reference is made to SAE Standard J1395. It was not until May 15 of this year that Standard No. 108 was amended to incorporate SAE J1395 (with an effective date of December 1, 1990). I en close a copy of that amendment for your information.

If you have any further questions, we shall be pleased to answer them.