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New member here and I hate to introduce myself with a question but I have one anyway.
A week ago last Saturday I bought a 2006 F250 Lariat Crew Cab with the 6.0 and 4WD. The truck is really clean and only has 68,000 miles on it. Here's my question: I needed to tow a boat today and I discovered I have no power, at all, at the trailer light plug receptacle. Nothing at the 7-pin nor the flat-4. I looked through the manual and checked every fuse that had the word trailer associated with it and I can also feel the turn signal relays clicking with the flashers on.
Am I missing something really simple or do I just need to follow the wire harness from the back and look for something that is not connected? It seems kind of weird for it to be just....dead.
I really need to get this boat moved so I am looking for any tips anyone can offer.
Pull a diagram on the wire harness. They are all pretty standard. Once you find a diagram use a meter and start testing the wires for resistance, can also check for voltage with the truck running. Pretty sure the 4 pin harness is spliced off the 7 pins though.
These wiring diagrams are great! Do they also apply to a 99 7.3 SD? Do I really have to start by pulling apart the main junction box and removing the dash?
So the next morning I found a different round-7 to flat-4 adapter with the small red indicator lights that I had laying around the garage. Plugged it in and all the lights lit at the proper time. So I went back and re-checked the trailer and found a spot where the trailer wire insulation had worn through. I spliced in a new section of wire and all was fine. I feel kinda stupid that I missed it.
The LED trailer light tester worked on my van, even though there wasn't enough voltage to operate the trailer lights.
I built a tester that has incandescent lamps, for the trailer running lights, to show what is really going on.
I made a mount to attach it to my tripod.
I plug it in and stand it beside the truck, so I can see it in the mirror.