Brake Controller Power Wire Missing on 2009 GMC Sierra

Question:

2009 GMC Sierra Thanks for the excellent videos! My issue is that I can only locate one wire under the hood near master cylinder which goes to the 6mm post its red with black tracer. Looks as if the trucks previous genius owner had controller installed because I see cut wires under the dash. I have a factory 7pin connector and am installing the teconsha voyager. No light with everything except the 8mm power connected. Where does the 8mm power wire come from/go to? I think I will have to run a new wire. Have a long distance camping trip with my family in 2 weeks and Im freaking out now on what looked to be an easy install.

asked by: Chris L

Helpful Expert Reply:

It is possible that the previous owner was not aware of the tow package wiring and connections that need to be made under the hood of your 2009 GMC Sierra. The tow package power wire under the dash essentially goes directly under the hood over by the power distribution box. If it is present then it might be there off to one side.

If not then there is no reason why you can't run your own wire from the brake controller to the positive post that the factory wire would normally attach to. You would just need maybe 5 feet of wire like # 12-1-1, sold by the foot, and a ring terminal, # DW05741-1. Then you would splice the new wire to the black brake controller wire, route it through the firewall, and over to the brake controller post on the power distribution box. hook the ring terminal on that post and tighten down the nut, # 185917.

expert reply by: Michael H