Getting 12 Volt Power to 7-Way Trailer Connector on a 2003 GMC Sierra

Question:

what do you have to do to get accessory power to the factory trailer connection. the manual is unclear. what needs to be connected at the fuse box that is under the hood to energize the circuit

asked by: David P

Expert Reply:

To get the 12 volt circuit working on the 7-Way trailer connector on your 2003 GMC Sierra you will first need to go under the hood and remove the covers on the power distribution box.

After removing the main cover and the cover under that you will see a post on the passenger's side front corner. There will need to be a 40 amp fuse in the nearest location to that post. If there is no wire attached to that post then you will need to follow the help article I have linked to the right.

Step F mentions a bonded wire that is included. You can ignore that. If there is no wiring to the post you will need to run it manually using about 20 feet of wire # 12-1-1. It will go from that front post all the way back to the back of the 7-Way trailer connector and attach to the back in the 11 oclock position.

expert reply by: Michael H