Interpretation ID: 2660o
Manager, Automotive Lighting
Engineering Dept.
Stanley Electric Co. Ltd.
2-9-13, Nakameguro, Meguro-ku
Tokyo 153
JAPAN
Dear Mr. Arisaka:
This is in reply to your letter of September 23, 1987, with respect to daytime running lamps (DRLs).
With reference to the Canadian proposal on this subject, you have noted that it would allow optically combining the DRL with the parking lamp, using dual intensity bulbs within the same housing and covered by the same lens. (As you may be aware, the Canadian government recently issued a final rule which adopted the proposal). You have further noted that the maximum candela output of the parking lamp together with the candela of the DRL will be greater than the maximum permitted for the parking lamp. You believe that under this circumstance the parking lamp does not have to conform to the maximum values specified, and have asked for our opinion of this matter.
Under the proposal by the United States, a DRL would have to be a lamp other than a parking lamp (proposed new paragraph S4.6.3(a)), because their brightness is inadequate for use as DRLs. However, the DRL could be incorporated into a multiple function lamp, one of whose functions is to serve as a parking lamp. A lamp with multiple functions must meet all requirements that apply when a specific function is being fulfilled. For example, a lamp that functions both as a parking lamp and a DRL and which is operated in daylight could act as either a DRL or a parking lamp, depending on the intensity of the light emitted, but it would have to meet the photometric requirements for the function being exercised. We cannot really be more specific in answering your questions, because we are still at the proposal stage of the rulemaking process. The final decision could differ.
Sincerely,
Erika Z. Jones Chief Counsel ref:108 d:2/19/88