Interpretation ID: nht89-2.41

TYPE: INTERPRETATION-NHTSA

DATE: 07/24/89

FROM: STEPHEN P. WOOD -- NHTSA ACTING CHIEF COUNSEL

TO: DAVID S. HUGHES

TITLE: NONE

ATTACHMT: LETTER DATED 03/24/89 FROM DAVID S. HUGHES TO ERIKA Z. JONES -- NHTSA; OCC 3354

TEXT: Dear Mr. Hughes:

This is in reply to your letter with respect to a lighting fixture you wish to install on your trailer. Your diagram shows it to be a rectangular unit that displays "Thanks Driver" or "Thank You" as a courtesy message. The unit may be mounted on the re ar of the trailer, "between the safety bar under the floor of the trailer", or "directly behind the mud flaps." In either location, you state that it "would be out of the way of any regulated light." You are also interested in the possibility of selling the lamp. I regret the delay in responding.

This agency has no authority to "approve" or "disapprove" individual items of lighting equipment. We can, however, advise you as to the relationship of your device to the Federal motor vehicle safety standard on lighting administered by this agency, and the National Traffic and Motor Vehicle Safety Act under which the standard was issued. With respect to your installation of the lamp on your own truck, this agency has no regulations that would govern such an action. The acceptability of this device w ould be determined under the laws of the individual States in which a vehicle so equipped is registered and operated. We are unable to advise you on State law and recommend that you contact the American Association of Motor Vehicle Administrators for gu idance, at 4600 Wilson Blvd., Arlington, Va. 22203.

We assume that your interest in selling the lamp is as an aftermarket accessory to truck owners. If the lamp is installed by the owner of the truck, once again there are no Federal standards that apply to it, only the laws of the individual States. How ever, if the lamp is installed by a manufacturer, distributor, dealer, or motor vehicle repair business, under Federal law its installation must not render inoperative, either in whole or in part, any of the lighting equipment required by the Federal lig hting standard. To aid these parties in avoiding a violation of that prohibition, you should ensure the wiring does not interfere with the

effectiveness of the wiring of lamps installed in accordance with Federal requirements. Without a photo, we are unsure of the relationship of the location of the courtesy device in either of the two locations you have suggested to the location of other rear lights required by Federal law, such as identification lamps, clearance lamps, stop lamps, turn signal lamps, etc., though you have stated that it is "out of the way" of them. However, your statement indicates that you recognize the importance of e nsuring that the signal from a supplementary lamp not dilute the effectiveness of Federally-required lighting equipment, and we appreciate your concern.

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

Sincerely,