Can Brake Controller Cause Check Engine Light To Come On

Updated 11/16/2015 | Published 11/15/2015

Question:

Hi I recently purchased a 2005 Silverado and it has the Reese brakeman digital unit in it. I was just wondering how I can adjust it to the lowest level so it doesnt effect the truck... I will not be towing anything where that will be needed. I was messing around with the sync control on the side and the dial on the top last night as I was driving and when I started up this am I had a check engine light. Im not sure if its related but thats why Im on here ..any information you give me can help. Thanks

asked by: Mike

Expert Reply:

If the brake controller was properly installed, it shouldn't be able to affect the vehicle in any way that would cause the Check Engine light to illuminate. The only connections to the vehicle systems that the controller has is the power feed and the connection to the stoplight switch that tells the controller when the brake pedal is being pressed. I believe that the timing of the engine light coming on not long after adjusting the controller is purely coincidental.

Since you're not planning on needing the controller any time soon, I'd recommend unplugging it. The controller should be wired to a harness that plugs into a gray connector under the dash. Simply follow the wiring harness exiting the rear of the controller until you find the connector.

I've linked you to some FAQ articles about brake controllers.

expert reply by: Mike L