Brake Controller Always Applies Trailer Brakes When Connected Troubleshooting

Updated 03/17/2020 | Published 06/23/2015

Question:

2008 Chevy Silverado I added a brake controller and hooked up everything correctly. However, the factory light/blue wire that is the brake signal wire has current to it all the time causing the brakes to apply all the time as if the pedal is pushed. Is there a relay somewhere that could be bad causing this? Any ideas on how to troubleshoot the issue. i thought about just tapping the wires coming of the brake switch beside the pedal. The brake lights all work correctly, just the trailer brake signal wire stays hot and only if the ignition is on.

asked by: Ben

Expert Reply:

You will need to use a different wire for the stop light circuit for installing your brake controller. You need to find a circuit that has 12 volts only when the brakes are applied.

The easiest place to find this circuit is at the brake pedal switch like you mentioned.

expert reply by: Jameson C

Jayson W.

3/15/2020

I had the same exact problem on my 2011 avalanche I got under the dash fiddled with the brake switch. The white with blue wire at the bottom is the one feeding the brake controller. I can move it around and watch the controller power come on before the brake lights themselves. Move the switch around until the power is off at that wire

Chris R.

3/16/2020

If I'm understanding correctly it sounds like you were able to resolve the issue (let me know if I'm wrong). Are you saying that you simply tapped into the brake switch wire at a different location (further up or down the wire)?

Jayson W.

3/16/2020

No I changed my brake switch itself and the factory trailer wire worked like it should. The Blue and white wire with the factory harness. It also fixed my speratic cruise control problem

Chris R.

3/17/2020

I gotcha! Thanks so much for the info and I'm glad you were able to get it all sorted out. We really appreciate this kind of feedback (and so do our other neighbors dealing with the same kind of issues).