Locating Factory Brake Controller Wiring on 2012 GMC Sierra

Published 08/08/2018

Question:

Ive watched the videos, but I cant find the wires that are above the break. They are not there. The manual says they should be there. Instead it seems that I have a hook up, plug, above the emergency break that might be the correct hook up as it has five wires. I cannot find a wire with the correct preconected end. So Im not sure if theses are the correct wires to hook up the trailor break system too. Is this hook up for the factory installed breaking system? And if so how do I connect to it? Thanks .

asked by: Spencer M

Helpful Expert Reply:

Your 2012 GMC Sierra is not equipped with a factory brake controller port for a simple plug-in installation, but all the necessary wires are indeed already run to beneath the dash so that it is just a matter of connecting the 4 wires from the brake controller to the factory wires on the truck.

These wires should be on the driver's side in front of the fuse panel to the left of the brake pedal. They will likely be taped to other wiring and you will just need to pull them free. There should be 5 wires and it looks like they will be red, dark blue, light blue, white, and orange. The orange wire will not be used.

The red wire on the truck will connect to the black (12V power) wire on the brake controller. The dark blue truck wire will go to the blue (brake output) wire on the controller. The light blue wire goes to the red wire (brake input) on the controller and the white wire goes to the corresponding white wire (ground).

I have attached an installation video on the 2011 Sierra that you can use for reference, along with an article that will walk you through the process.

expert reply by: Chris R