Interpretation ID: 2805yy
Manager, Engineering Services
Oshkosh Truck Corp.
P.O. Box 2566
Oshkosh, WI 54903-2566
Dear Ms. Zeitlow:
This is in response to your letter of December 21, l990, to Taylor Vinson of this Office, in which you ask a question about Federal Motor Vehicle Safety Standard No. l08. You have also asked for confirmation of your understanding with Mr. Vinson with respect to three other aspects of motor vehicle safety regulations of the National Highway Traffic Safety Administration.
With respect to Standard No. l08, you believe that our letter to you of August 27, l990, stated that "the hazard warning signal should always override the stop lamp signal when both are red in color." Mr. Vinson, by telephone on October 9, said that he believed that at some time previous the override feature had been at the option of the vehicle manufacturer. You have asked the date that Standard No. l08 changed, and "in which section of the regulations can I find the ruling."
Actually, our letter of August 27, l990, did not state that the hazard warning signal should override the stop lamp signal. We explained that Standard No. l08 requires a turn signal lamp to override the stop lamps if the lamp optically combines stop and turn signals, and that because the hazard system operates through the turn signal lamps, the stop signal cannot be turned on in an optically combined lamp if the hazard system is in use. The specific wording of the regulatory requirement is "When a stop signal is optically combined with a turn signal, the circuit shall be such that the stop signal cannot be turned on in the turn signal which is flashing." You will find this in paragraph 4.2 of SAE Standard J586c Stop Lamps August l970, and in paragraph 4.4 of SAE Standard J588e Turn Signal Lamps September l970, both of which are incorporated by reference in Table I and Table III of Standard No. l08. And a vehicular hazard warning flasher is a device which causes all the required turn signal lamps to flash; see Definition in SAE Recommended Practice J945 Vehicular Hazard Warning Signal Flasher February l966, also incorporated by reference.
We note that this regulatory requirement was not originally contained in Standard No. l08. The predecessor SAE Standards J586b June l966 and SAE J588d June l966 originally incorporated in Standard No. l08 did not include override language. Standard No. l08 was amended on January 5, l976, to incorporate SAE J586c and SAE J588e, with an immediate effective date, but allowed compliance with the older standards until September 1, l978 (41 FR 765). Thus, during the period January 5, l976, to September 1, l978, a manufacturer had the option of providing the override feature in a combination lamp in which the hazard and turn signal functions used the same circuit.
You have also asked whether a sun visor is required by the Federal motor vehicle safety standards. The answer is no, if the vehicle is a truck, bus, or multipurpose passenger vehicle with a GVWR that exceeds 10,000 pounds. However, if the GVWR of those vehicles is l0,000 pounds or less, or if the vehicle is a passenger car, paragraph S3.4 of Standard No. 201 Occupant Protection in Interior Impact requires that a sun visor be provided for each front outboard designated seating position.
In addition, you asked whether any regulation specified the type or quantity of horns required on a motor vehicle. The answer is no. Standard No. 101 Controls and Displays does not require that any motor vehicle be equipped with a horn. However, if a horn is provided, it is subject to the requirements of the standard for horn control location, identification, and illumination.
Finally, you asked whether Standard No. l04 Windshield Wiping and Washing Systems contains "the percentage of area of the windshield that the windshield wiper must wipe", or specifies only the frequency of the wipers. Standard No. l04 does not specify wiped area percentages for windshield wiping systems on multipurpose passenger vehicles, trucks, or buses. However, it does specify percentages for passenger car systems, and it specifies the frequency for all motor vehicle windshield wiping systems.
I hope that this answers your questions.
Sincerely,
Paul Jackson Rice Chief Counsel
ref:l0l#l04#l08#20l d:l/l6/9l