Interpretation ID: 17258.ztv

Mr. Eric Williamson
Accessory Department
Accessories Sales & Marketing
Gulf States Toyota, Inc.
7701 Wilshire Place Drive
Houston, TX 77040

Dear Mr. Williamson:

This is in reply to your letter of February 16, 1998, with respect to rear deck spoilers incorporating center highmounted stop lamps (CHMSLs).

The spoiler with its lamp is designed for installation on vehicles whose original CHMSL is located in the rear window. This raises the question of whether the original CHMSL should be disconnected when the spoiler incorporating the new one is installed.

By way of background, and to be brief about it, modifications may be made to new vehicles before their initial sale as long as the vehicles remain in compliance with the Federal motor vehicle safety standards to which their manufacturers have certified them. Because the addition of a spoiler may partially block the light output and visibility of a CHMSL located in the rear window, resulting in a noncompliance with the Federal motor vehicle safety standard on lighting (Standard No. 108), we have advised that, under these circumstances, a second CHMSL should be added that meets original equipment requirements. When the second CHMSL is added, the original CHMSL then becomes merely a supplemental stop lamp. Supplementary lighting is permitted under Standard No. 108, provided that it does not impair the effectiveness of any lighting equipment required by Standard No. 108. We do not believe that a supplementary CHMSL in the rear window impairs the effectiveness of a spoiler-mounted CHMSL.

This means that, under Standard No. 108, there is no Federal law requiring the original CHMSL to be disconnected. However, Standard No. 108 does not apply to the use of vehicles on the public roads. Some states may require the original CHMSL to be disconnected when a spoiler-mounted CHMSL is provided. We are sorry that we are unable to advise you on the laws of the individual states.

We note your comment that the spoiler includes "a D.O.T. approved rear brake lamp." This phrase is often mistakenly used to indicate a lamp that is designed to conform to the requirements of Standard No. 108. We assume that you meant a center stop lamp that will comply with all requirements of Standard No. 108 when it is installed on the vehicle. D.O.T. itself has no authority to "approve" or "not approve" any item of equipment and the phrase "D.O.T. approved" has no meaning and should not be used.

If you have any questions, you may refer them to Taylor Vinson of this Office (202-366-5263).

Sincerely,
John Womack
Acting Chief Counsel
ref:108
d.4/8/98