Question:
I have a 2005 gmc 2500hd 4x4. on my 7 way connector-truck side, all the plugs are getting power except for the one marked +. on the trailer side this is the hot, which i do believe controls the interior dome lights on the trailer. all other lights and brakes work on trailer, just not the interior. also, on the truck side, the + on the plug, has a red wire going into the back for the +. all fuses are good, the only thing i noticed was that stud 1 has no fuse in it. stud 2 has a 30 amp. any reason why i am getting no power to +, or am i just overlooking something???? thanks in advance for the help.
asked by: Joe C
Expert Reply:
I think your problem is in the power distribution box, under the hood, on your 2005 GMC 2500 HD. You will need the 40 amp fuse installed by stud 1 to activate the power to your 7-way at the rear of the vehicle.
The power post closest to the firewall of the vehicle should have a wire attached to it that will connect to the black power wire on the rear of the brake controller and a 30 amp fuse installed next to the post.
The power post closest to the front of the vehicle should have a wire attached to it that will run to the 7-way at the rear of your vehicle and connect to the 12 volt power pin ( + ) and a 40 amp fuse installed next to the post. The fuses do need to be installed to activate the power posts.
I am including a link to a FAQ page on brake controller installation for the 1999 to 2006 Chevy/GMC Trucks. It will show in step 2 the power distribution box connections.
expert reply by: Jeff D

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Product Page this Question was Asked From
Pollak 7- and 4-Pole Trailer Connector Socket w/ Mounting Bracket - Vehicle End
Product Summary:
Trailer Hitch Wiring
No Converter
Custom Fit
Product Specs:
7 Blade
4 Flat
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