I have a 98 f150. I am in the process of replacing the 4 flat wiring connector because a pin broke off.

I change the connector and in testing the trailer lights I found the running lights tail light/running lights were not coming on. The turn signal and brake lights work. I jumped the tail lights and they worked. The trailer has LED lights.

I checked my work and all is fine.

Is there a separate fuse just for the trailer tail/running lights.

I have no experience in wiring. How do I trouble shoot this.

 

I can't remember what my 98 had but my 05 has separate fuses for the turn signals and the running lights for the trailer hook up.

 

Yes, there are separate fuses. If you don't have the owner's manual, download it.

 

Yes, the 97/98 has both a relay and a fuse for the parking lamps.

Start with the fuse, Engine compartment Fuse #1 20A
- This feeds both the trailer tow parking lamp relay and the trailer tow backup circuit.

The relay for the parking lamps, you can see documented in this thread

https://www.f150online.com/forums/4803710-post17.html

 

Got home last night and found the manual. Your are right is was #1. Put in new fuse and all is well. Probably blew due to the weakening of ground pin on truck side of 4 flat. It felt lose and so I changed 4 flat.


Confused me, didnt think of a separate fuse at first and didnt want to dig into wiring.

Thanks all.