I recently bought a used '71 F-150 to take hunting, and haul my just as old Rocky Mountain camper. The truck had a plug already wired in, but the colors didn't match the camper so I tested them first and I don't get it. There are 3 wires + a ground. This is what I got;
yellow= was the only wire that was hot when left turn signal was on, but also lit up for the right turn, brake and park lamps.
Red= was hot for the right turn, brakes and park lamps.
Green= was hot for tyhe brakes, and the park lamps.
My Camper has a red,a green,a blue and a white wire, (ground I thought) with the blue wire running inside to the fuse panel, which I thought was for the interior battery operated lights.
So please someone, please tell me what goes to what ?
I've already missed 2 days of hunting.
Thanks

 

I don't have a diagram for a 71 truck. I do have access to a 71 car, which may or may not be the same. It uses brown for the parklamps, lightgreen/white for left turn/brake. and white/lightblue for rightturn/brake.

What we need is a little bit clearer picture of what's going on. Is this a slide in camper in the truck bed or a trailer? In either case, do the truck's lights work correctly? Where is this wired plug located and tapped into the wiring harness of the truck?