BAC Forum

General Boards => Technical Support => Topic started by: Paul Aronson on August 18, 2018, 02:23:26 AM

Title: Check engine - brake switch problem
Post by: Paul Aronson on August 18, 2018, 02:23:26 AM

I recently had the check engine light come on while driving on the Interstate. Light cleared after stopping the engine when refueling. Stopped at a repair shop and the engine had a "brake relay fault" code showing as nonactive.
Brake lights work fine, problem has not reappeared.
Can anybody tell me what causes this code to appear? I can find the stop light relay in the wiring diagram but cant follow it far enough to determine what causes the fault code.
Any help?

Title: Re: Check engine - brake switch problem
Post by: Gerald Farris on August 18, 2018, 02:57:26 AM

Paul,
A check engine light for a brake relay fault has nothing to do with your stop lights. It is related to your engine compression brake otherwise known as a Jake Brake.

Gerald

Title: Re: Check engine - brake switch problem
Post by: Paul Aronson on August 18, 2018, 07:15:19 PM

Thank you. I'll call Caterpillar onday and see if they can give me any specifics to look for.