Good morning. I'm a few years late to this thread, but hoping someone sees this. I have a 1997 Suburban and am wanting to go from a 4-flat to a 7 pin to provide 12v to my trailer for interior lights. I saw another thread last week (but I can't find it now) that mentioned a "light duty" & a "heavy duty" harness that are pre-installed at the factory. I understand the orange and blue wires and have already located them. My concern is what I am finding at the rear of my vehicle... the accompanying pics show what the existing connection is and the bundled wires on the drivers side. My questions are, 1) Is what is connected the "heavy duty" harness? 2) Why does the bundled group appear to have a larger white (ground?) wire? Thanks for any input.
You should have a rear wiring connector under the bed (I expect the pic you loaded is that connector). You can buy a 7 pin harness that will plug into that connector. That will provide the outside trailer lights.
But, you may need to run wires, to the connector, for the inside trailer lights (12v aux) and brakes if you need 'em.
A forum community dedicated to all General Motors truck owners and enthusiasts. Come join the discussion about performance, lift kits, wheels, tires, modifications, troubleshooting, maintenance, and more!