Tow Package Wiring Connections Under the Hood of a 2001 GMC Sierra with Factory 7-Way

Updated 11/07/2016 | Published 11/05/2016

Products Featured in This Question

Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers - GM

(484)

$18.53

10 Gauge Wire - Blue Primary - Per Foot

(104)

$1.78

Hook Probe Circuit Tester

(62)

$13.94

Question:

I have a 2001 gmc sierra, has factory 7 way in back, I have purchased the Tenoshka P3 and the adapter harness. installed the controller and harness and no power to the trailer brake controller, found a priveous question about making the connections under the hood, and installed a 30 amp fuse and the red ringlet to the power point. Now I have the trailer brake controller has power, But I am wondering what to do with the Blue wire with the factory connector, every video and instruction has you cut the connector and but connect the connection to the white wire that you have ran from the back of the truck, Hence I have a factory 7-way connector so I have not ran a wire from the back of the vehicle. I do not have a trailer with me to try to see if the trailer brake controller is functioning correctly.

asked by: Cory B

Expert Reply:

First, you can see if power is getting back to the 7-Way by having someone sit in the truck and apply the manual override lever on the brake controller. While they are doing that use a circuit tester such as # PTW2993 or a meter if you have one to test the pin in the 5 o'clock position on the 7-Way.

If power is getting to that location when testing, then the connection is already made, and you won't have to do anything. If the there is no power, you can run a wire manually from the blue brake controller wire (the one under the hood should be connected to the port where the brake controller harness plugs in) back to the back of the 7-Way in the 7 o'clock position. Use 10-gauge wire # 10-1-1 which is sold by the foot.

If that blue wire under the hood does not have power when the manual override is used then you would remove the blue wire from the brake controller harness from the end that plugs into the truck, attach one end of the 10-1-1 wire to it, and route the other end through the firewall and back to the 7-Way as described above.

expert reply by: Michael H