Troubleshooting a Reliance Brake Controller That is not Operating Correctly

Question:

I plugged in my harness on 2001 gmc 2500 and when I push brake e1 dont come on when push the button on controller e1 comes on and so does the door dinger

asked by: Rick

Expert Reply:

It sounds like the brake light switch wire coming out of the brake controller may be wired into the wrong circuit.

If you have the older C/K body style with the square shaped front body, then you will need to double check that you have the red wire connected to the brake light switch wire. The wire on the brake switch that needs to be connected should be a light blue wire according to the installation instructions for the Reliance controller. You can use a tester, like # PTW2993, to help find the correct brake switch wire. When under the dash, probe the wires around the switch. When a signal is present when the pedal is pressed, that will be the wire you need to tap into for the controller.

You may have a wiring port on your 2001 GMC that you can wire and plug into for your brake controller. If your vehicle is a Sierra model with a rounded front body style, then you will have the port located to left of the emergency brake pedal. If this port is present, then you remove the wire splices you may have made and wire direct into your truck's wiring through the port. You will use # 3025-S harness to wire to your brake controller plug then plug the other end in port that is described in the linked article at the bottom of the page.

expert reply by: Jared P