I'm having a problem with my factory installed trailer plug. It's the regular 4 pin connector. Somehow I've lost the running light output. I know it's not the trailer because not only did I test each circuit on the trailer with a 12 vdc power supply, I hooked up another truck and everything on the trailer is ok. My turn signals, hazards, and brake light outputs work fine. I checked and cleaned the grounds to make sure nothing was loose or dirty. All is ok. But when I turn on the headlights the trlr lights do not come on. The brakes/turn sig's etc work fine. I don't have an operator's manual for my vehicle so I don't know if there is a fuse that I can check or where the wiring harness terminates. Can anyone offer a suggestion of what I can check next or where online I can get a printout of my fuse panel?

Thanks,

Doug Greig
S. Burlington, VT
97 Expedition XLT 4x4

 

Yeah i got the same problem, i checked all the fuses i could and still nothing , can someone out there help?

 

Hi Doug

I dont have fuse diag...hopefully its just a blown fuse?

Dont know about 4 pin...but 7 pin have both fuses/relays.

So...as you already know...gotta find fuses for the 4 pin plug...also look carefully around the underhood fuse box..there maybe another small fuse holder...it might even be taped over?

Maybe someone here can help more. Keep checkin.

Good luck...OT

btw... www.helminc.com sells OEM manual for your truck.

 

Thanks for the link. I'm definitely going to order a manual. As for my problem, I did some research on this site and found exactly what I was looking for. There was a blown fuse located under the hood. It was one of those REALLY small ones and not labeled either. After a quick trip to the autoparts store the problem was solved.

Thanks,

Doug Greig