Interpretation ID: nht87-2.12

TYPE: INTERPRETATION-NHTSA

DATE: 06/17/87

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: MMC Services Inc.

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. Nobuyoshi Takechi Technical Manager MMC Services Inc. 3000 Town Center Suite 1960 Southfield, MI 48075

Dear Mr. Takechi:

This is in reply to your letter of April 24, 1987, with reference to the legality of a proposed concealed headlamp design. As we understand the proposed design, the headlamp could be used in the "concealed" position as a forward warning (which you believ e "is similar to the daytime running light principle" and "is useful to avoid accidents") and in the unconcealed position as a headlamp to provide visibility of the roadway ahead. A portion of the vehicle body in front of the concealed headlamp would be clear, allowing the beam from the concealed lamp to shine through it. The steady burning forward warning signal would be given by pulling a spring-loaded switch. Releasing the switch would turn off the headlamp. Thus, the concealed headlamp would not, as a practical matter, be used for providing visibility of the roadway ahead but as an alternative to the vehicle's audible warning device, the horn. The proposed use would be a visual "horn." Finally, you state that the beam pattern and intensity of the l amp "is corresponding to the headlamp's," although you do not explain how this is possible, given the potential for interference from the vehicle's body.

Standard No. 108 prohibits covers or other styling features in front of a required headlamp when it is being used for purposes such as illuminating the roadway ahead or increasing the visibility of the vehicle in conditions of reduced visibility. We do n ot consider this prohibition applicable when a headlamp is being used, in all likelihood momentarily, for forward signalling as described. Further, use in this manner would not appear to impair the lighting equipment required by the standard. Additionall y, headlamps may be wired to flash for signalling purposes, as you have proposed, however, we are unable to advise you whether operation of this device is acceptable under the laws of the individual States. Your letter does not indicate whether the beam utilized is the upper beam or the lower beam; some jurisdictions such as the District of Columbia and Virginia prohibit use of the upper beam for signaling purposes. Others may restrict use of headlamps or a portion of them during daylight hours; we expe ct to learn more about this in comments to the docket on the daytime running lamp proposal. In the meantime, I would advise you to write the American Association of Motor Vehicle Administrators, 1201 Connecticut Avenue, NW, Washington, DC 20036, for its views on State laws.

You have stated that this use "is similar to the daytime running light principle." However, as proposed by the Government of Canada, and by the U.S. Government in the Federal Register (52 FR 9316) such "DRLs" would be automatically energized, and not ene rgized at the driver's choice as is your device. Therefore, we do not view the operation of your device as similar to the daytime running light principle.

Sincerely,

Erika Z. Jones Chief Counsel

April 24, 1987

Ms. Erika Jones, Chief Counsel NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION U. S. Department of Transportation 400 Seventh Street, S.W. Washington, D.C. 20590

Dear Ms. Jones:

MMC has been developing concealed headlamps for application to our future models. (See attached). In this design, a portion of the body in front of the concealed headlamps is replaced with a clean material. This will allow the driver to give a steady-state forward warning without having to open the headlamp. The driver gives a forward warning by pull ing a spring-loaded switch, such as the headlamp upper/lower beam changing lever, and the headlamps are turned off by release of this switch. The photometric performance (beam pattern and intensity) is corresponding to the headlamp's.

We believe this function is similar to the daytime running light principle, is useful to avoid accidents, and we find no regulations prohibiting such system.

Please provide us with your opinion as to the legality of this system.

If you have any questions, please contact me at (313) 353-5444. Very truly yours,

Nobuyoshi Takechi Technical Manager

NT/sg MMC SERVICES, INC.

Enclosure