has anybody had problems with the lighting for trailer lights? The lights on my trailer work. had my frind hook his truck up to it and they work fine. when i hook my truck up to it i only get the running lights to work. No brake lights or turn signals. I use the 4 way plug it looked corrided so i replaced it and still nothing. Checked fuses there all good. Checked the wires from 4 way to the ground on the truck there all good. I even cleaned the ground connection and still nothing. Anybody have this before or know of anything to look for in particular. Im going to try to test the wires tomorrow when i get some time. So any tips will help. thanks

 

I had the same thing on 99 F250. I had been going round and round looking @ wiring and could not figure it out.

I decided to change the fuse even though it looked fine. Problem solved.

On mine it was the #4 fuse in the distribution box under the hood.

 

I changed the fuse under the dash the 10 or 20 amp can't remember. But I never looked under the hood for one ill have to check that. My truck is a 02

 

All your fuses on the '02's are under the dash.