The trailer lights went out on my boat trailer for almost no reason, there were no shorts. I traced the problem to the connector on back of my 04 Ford F250 Diesel. The wires were dead, except for the running lights. After spending hours tracing and pulling apart harness connectors underneath the truck, I finally determined that the problem was up front. Even though the truck is under warrantee, I hate to visit the service department, it is one heck of a in-convenience, I came here instead. This is what I learned.

Late model Ford trucks have seperate fuses for the trailer connector, you know the one located near the hitch. (different than other vehicles that I owned) It seems that these mini fuses, even though they have a rating similar to the big ones, seem to blow for almost no reason. After reading above, my problem was quickly determined to be a 20 amp fuse. On the late model F250s, the fuse box is located inside the cab, to the left of the steering column, behind a large compartment cover secured with four plastic pop out screws. I replaced the 20 amp mini fuse and "wala", the trailer lights work.

Probably a good idea to keep plenty of mini fuses on hand, several sub-circuts are protected with mini fuses. Glad this web site was here, saved me from another trip to the service depart. I'll talk about the super sensative seat belt retractors, you know, the kind that lock up and trap you, perhaps this one is best left for another forum.

algutkin