Need Wire Info. for Trailer Brakes - Diesel Forum

66hybrid · 07-11-2009, 06:27 PM

1. My 1993 F250 has the four prong quick plug under the dash
2. The power distribution center on the inner fender has fuses for trailer brakes and battery charging.
3. The truck has a very hefty 4" reciever

There is no 4 or 7 prong plug in the rear! Everything looks original and nothing has been spliced. The OEM harness has five wires. None of the five look like the trailer brake or charging wire. Where are they? I assume they are somewhere since the distribution center has them listed and fused.

chuckster57 · 07-11-2009, 06:46 PM

My prodigy has a four wire harness on it. I don't remember how it's hooked up but if you go to tekonsha.com you can down load the wiring diagrams. IIRC the wires are universal in coding. As far as the plug at the back of the truck, It may not have ever been put in. You can look under the bed for a harness that terminates near the bumper. My '86 had the harness and I had to add the plug and wires.

Trailer Wiring Diagrams

Here is where you can see the different plugs and the schematics. Hope this helps