Brake Controller troubleshooting on a 2003 Suburban 1500 4X4

Expert Reply:

If the Draw-Tite 2-4 Brake Electronic Brake Controller, item # 5100, is applying the brakes with the slider and not when you step on the brake then this is showing that you have power to the brake controller through the black wire and that the blue wire going to the trailer brakes is connected. This means that the input from the brake pedal switch must be the problem. Make sure that the brake controller is grounded properly and test the red wire going into the controller with a circuit tester, item # 3808 if needed. You should get power through this circuit when the brake pedal is applied and there should be no power when the brake pedal is not pressed. If you are not getting power through the red wire then you may have an improperly wired adapter for your vehicle (see below). If you do have power going in when the pedal is pushed and no power coming out check the power setting, if this is not the problem the controller must have an internal problem. Brake controllers are not user serviceable. Your suburban uses a Universal Brake Control Wiring Adapter 2003 - 06 Chevrolet, GMC, Cadillac, item # 20264, which should have the red wire in the bottom right corner looking at the connection side of the connector, with the locking tab in the down position. If your red wire is in the top left position then you will need to move it to the bottom right position by removing the blue locking clip and pressing on a very small locking tab on the connection side of the terminal,with a small screwdriver to remove the wire and install it into the correct port on the connector.

expert reply by: Bob G