Troubleshoot Brake Controller in 2007 Chevy Silverado where Controller only Works with Lever

Question:

I got this controller and it has been wired to the factory harness. In my buddies 07 Silverado classic 1500 it works fine with his rv In my 07 Silverado classic 2500hd, I get a red light when manually activating the brakes, but not with the pedal. Is there a difference in the wiring of the two? On my truck, the black wire is currently hot based on the circuit tester on the 6 pin conductor under the dash. The diagram shows that should be red. Also, when I check the 6 pin conductor under the dash, I do not get an additional power signal when stepping on the brake pedal. Thanks

asked by: Phil C

Helpful Expert Reply:

With Chevy trucks like yours this problem is somewhat common. In almost all cases of this happening the problem is a blown third brake light fuse. When that fuse is blown the stoplight circuit for the controller stops working. Easy way to check this is to hit the brakes and see if the third brake light of the truck is working.

In the fuse box under the dash there will be a fuse for the circuit CHMSL which will need to be replaced.

expert reply by: Jameson C