Activate Trailer 12 Volt Power Circuit of 2007 GMC Sierra 2500HD

Published 12/11/2017

Question:

I have a 2007.5 GMC Sierra 2500HD I just bought a brand new snowmobile trailer and the interior lights do not working but blinkers 4 wats brake lights work.. I was told it was a fuse that’s supposed to control the interior light by giving them power but which fuse is it?

asked by: Kris W

Expert Reply:

If you look under the hood of your 2007 New Body GMC Sierra you'll see a fuse box on the driver side of the underhood area.

There are two wires under the hood that have to be connected to make the tow package functional, one is the power wire to the brake control and the other is the battery charge line to the 7 way connector. These wires are both Red/Black with eyelets on them. They are coiled up under the hood and will need to be connected to the under hood fuse box. One of the wires is located between the under hood fuse box and the left (driver) side fender. The other is located under the master cylinder/brake booster assembly.

See attached picture for more info on that.

expert reply by: Jameson C