Trailer Brake Controller Does Not Work with Brake Pedal on a 2001 Chevy Silverado

Question:

I just installed a P3 brake controller on my 2001 Silverado 2500HD with factory tow package. The controller is not receiving power when I press on the brake pedal. Everything else seems to be working fine including trailer brakes are being activated when the manual overide is used on the controller. I used the gm wiring harness and it plugged right into the box under the dash at drivers left foot. Is there something else I must do to get this to work properly when I apply the brakes on my truck.

asked by: Aaron T

Expert Reply:

When a brake controller works with the manual override but not with the brake pedal that indicates an issue on the red wire. Use a circuit tester like # PTW2993 and test the red wire. It should show power when you step on the brake pedal.

If it does not, then the first thing I would check is the position of the red wire in the connector that plugs into the truck. It should be positioned like in the picture I have provided. If it is in another location, then move it to the proper location.

If the plug is pinned out correctly then you could have a blown stop light or CHMSL fuse. Use the truck owner's manual to find the fuse locations.

If power is getting to the red wire then make sure the brake controller output is properly set. If nothing works, then that indicates a problem inside the controller causing it to not interpret the brake switch input properly so the brake controller would need to be replaced.

expert reply by: Michael H