How to Connect Brake Controller Wires to 2007 GMC Yukon XL

Published 04/16/2022

Question:

Hi, I have a 2007 Yukon XL It has a factory trailer plug at the back, but there are no wires for it under the dash. It looks just like a photo of a 2006 connection for a plug under the dash. Any help? The 7 way connector at the rear is connected to a factory wiring harness. No splices

asked by: Steve D

Expert Reply:

To install a brake controller, like the Tekonsha Primus IQ # TK90160, on your 2007 GMC Yukon XL you will need to locate the bundle of wires under your driver's side dash. So the wiring is already ran but there are just bare wires you splice to as opposed to a plug - this is somewhat common even on vehicles that come with a tow package.

I looked up the online version of the owner's manual for your Yukon XL and it looks like there is a section about this that mentions connecting a rad/black stripe power feed under the hood and then locating the blunt cut wires around the instrument panel. You will need to connect the following wires from your Yukon XL to the following functions on the brake controller:

Dark Blue - Brake Signal to Trailer Connector
Red/Black - Battery
Light Blue/White - Brake Switch
White - Ground

expert reply by: Jon G