Interpretation ID: nht80-1.23

DATE: 03/04/80

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Ross Frame & Axle, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your January 8, 1980, letter asking whether the computers connected to the air brake systems of trucks can be disconnected.

The computerized braking systems were used by some manufacturers to comply with the requirements of Standard No. 121, Air Brake Systems. Part of that safety standard was invalidated by the court in PACCAR v. NHTSA, 532 F2d. 632 (9th Cir. 1978). In that decision, the Court invalidated portions of the standard involving some of the road test requirements for trucks and trailers. The computer systems that you question were usually added for purposes of complying with the invalidated antilock sections of the standard.

The agency has previously addressed the question of whether the antilock systems can be disconnected in light of the court decision. Section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act (the Act) states that--

No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard . . . .

The issue is whether the antilock was "installed . . . . in compliance with an applicable . . . . standard." Because the NHTSA concluded that the "no lockup" and 60-mph stopping distances have been invalidated from the effective date of the standard, we also conclude that a manufacturer could not have actually been installing antilock systems or the brake performance levels in satisfaction of such a requirement, however much intended. Therefore, the NHTSA would not consider it to be a violation of @ 108(a)(2)(A) for a commercial facility to disconnect an antilock system or to provide instructions on how it can safely be disconnected. The NHTSA recommends that any modification be undertaken only after consulting with the manufacturer about the safest configuration of the particular vehicle.

SINCERELY

Jan. 8, 1980

National Highway Traffic Safety Admin.

Attn: Office of Administration

Dear Sirs:

I run a truck repair shop in southern Ohio. One of my customers has around thirty-five trucks. The largest percentage of these are equipped with the computerized braking system. Due to one accident and constant problems with the other trucks, it is their desire to disconnect the computers from their trucks braking system.

We have received word from the manufacture that this is now legal. My customer requests, in writing, a verification of this matter so they may turn it over to their lawyer for verification, so that in case of an accident, there will not be a law suit due to the disconnecting of the computerized brakes.

Any information you may have about this, please send to me so I may forward it on to my customer.

Thank you for your cooperation in this matter.

Joe Cain Ross Frame & Axle, Inc.