Interpretation ID: 1985-04.29

TYPE: INTERPRETATION-NHTSA

DATE: 11/18/85

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Mr. David Gruenzner

TITLE: FMVSS INTERPRETATION

TEXT:

November 18, 1985 Mr. David Gruenzner President, Future Tech Inc. P.O. Box 26B Mankato, MN 56002 Dear Mr. Gruenzner: This is in reply to your letter of September 23, 1985, asking for an interpretation of Federal Motor Vehicle Safety Standard No. 108 as it applies to an aftermarket high-mounted stop lamp/turn signal lamp system. You intend to market three models, as more completely described in the next paragraph. All models are mounted in the interior of the car. Our primary concern is the possibility that the interior-mounted unit will cause undesirable reflections in the rear window, reducing the ability of the operator to judge conditions to the rear of his vehicle as seen through the rear view mirror. For this reason, Standard No. 108 requires the new center-mounted stop lamps mounted on the interior to be provided with means to minimize such reflections. These lamps now in production incorporate shrouds that abut the rear window glazing. Though your after market device would not be prohibited by Standard No. 108 since it does not appear to impair the effectiveness of lighting equipment required by the standard, we encourage you to incorporate design features which will prevent undesirable reflections. Also care should be taken to ensure that, when the device is installed, it does not impair the field of view required for rear view mirrors by Safety Standard No. 111. Your device consists of eight miniature lamps, four mounted on each side of the vertical centerline. We also have some additional concerns about the operation of one of your three models. In the first model, in the turn signal mode, the lamps operate sequentially from the center outward in the direction of the intended turn. In the stop lamp mode, the entire unit will illuminate, "sending a sequential (sic) flashing beam from the middle to both sides." We view the sequential flashing of the lights from the center outwards in the stop lamp mode as prohibited by paragraph S4.6 of the standard which requires all lamps that are flashed for signaling purposes. However, the stop function in the second model is indicated by a steady-burning in use, except for turn signal/hazard warning signal lamps, and headlamps and side marker lamps that are flashed for signaling purposes. However, the stop function in the second model is indicated by a steady-burning light, thus complying with our requirements. In the third model, there will be an additional amber colored lens mounted on top of the red lens. The brake signal will be indicated by a steady red light, while the turn signals will be indicated by flashing amber ones. This method of operation is also acceptable under Standard No. 108 which permits rear turn signals to be either amber or red.

We are unable to assist you with State laws that may affect your devices. We suggest you contact the vehicle administrators in the States where you intend to market your system. I hope that this is responsive to your request. Sincerely, Original Signed By Erika Z. Jones Chief Counsel