Interpretation ID: nht90-2.75

TYPE: Interpretation-NHTSA

DATE: June 6, 1990

FROM: Tekonsha Engineering Company

TITLE: None

ATTACHMT: Attached to letter dated 8-31-78 from J.J. Levin, Jr. to L.F. Henneberger; Also attached to letter from F. Berndt to L.F. Henneberger; Also attached to letter dated 11-30-81 from F. Berndt to K.G. Moyer (A23; Redbook 3; Std. 108); Also attached to letter dated 9-10-90 from P.J. Rice to L.F. Henneberger (A36; VSA Sec. 103 (d); Std. 108); Also attached to letter dated 6-22-90 from L.F. Henneberger to P.J. Rice (OCC 4927); Also attached to Ford Bulletin Number 10, signed by R.R. Chestnut, dated 1 2-15- 89

TEXT:

By law vehicles towing trailers large enough to have a braking system must be equipped with a brake control device. Tekonsha Engineering is a major manufacturer of such a device.

The following is a brief overview of the use of the Commander Electronic Brake Control when the service brakes (foot) are applied initiating a stopping action the brake control activates both electrical braking systems simultaneously, illuminating the br ake lights and prompting a smooth stop. It is our understanding that it is a common practice to use the brake control's manual override (hand) to help control a swaying trailer. The brake lights do not illuminate while in this mode, thus eliminating fa lse braking signals.

We take pride in the fact that we make a diligent effort to engineer a product compatible with the ever changing vehicle electrical systems. The technological development of the Commander Electronic Brake Control was based on an extensive compatibility s afety study. We found that we could avoid the potential danger of interfering with the towing vehicles' electronically activated systems such as, the cruise control, the anti- lock brake system and the over-drive system by circumventing the electrical a ctivation of our device via the stop light switch. The enclosed Ford QVM Bulletin substantiates our efforts.

We feel the Commander's electrical non-interference factor to be a strong positive safety feature.