Brake Controller Wiring Identification on a 2007 GMC Sierra
Question:
The dark blue wire would attach to the blue wire coming off of your brake controller. The white wire would match up with the white wire. I would recommend using a circuit tester, part # 40376, to verify the function of the remaining wires. The light blue (which should show current only when the brake is pressed) would go to the red controller wire, and the red wire (which should show 12v with the ignition on) would attach to the black wire on the controller. The remaining wire is not used, and should show 12v when the headlights are on. I have added a link to a brake controller FAQ page that lists typical wire colors for brake controllers, but always use a circuit tester to double check.
asked by: Eric
Expert Reply:
The dark blue wire would attach to the blue wire coming off of your brake controller. The white wire would match up with the white wire. I would recommend using a circuit tester, part # PTW2993, to verify the function of the remaining wires. The light blue (which should show current only when the brake is pressed) would go to the red controller wire, and the red wire (which should show 12v with the ignition on) would attach to the black wire on the controller. The remaining wire is not used and should show 12v when the headlights are on.
I have added a link to a brake controller FAQ page that lists typical wire colors for brake controllers, but always use a circuit tester to double check.