How To Find The Correct Brake Signal Wire When Installing A Brake Controller

Question:

Installing an Energizer III onto a 2017 GMC Acadia with wiring harness . Everything works, just not getting a brake signal. Nothing from the Blue/White wire which, according to the owners manual, is the correct wire.

asked by: Joe O

Expert Reply:

It sounds to me like you are not splicing into the correct stop light circuit. The correct stop light wire you will need to attach the red wire from the brake controller to on your 2017 GMC Acadia is white. To test this, you will want to use a circuit tester like part # PTW2993. The first thing you will need to do is attach the circuit tester to the correct white wire located behind the driver side kick panel. Once attached, depress the brake pedal and the circuit tester should illuminate. If it does not illuminate, you will want to continue testing the wires with the brake pedal depress until you have located the correct stop light circuit.

expert reply by: Conner L