Check all your fuses in the truck. On my explorer (yes also a Ford) there
is a seperate fuse powering a set of relays that operate the trailer
interface cable. I can hear them click only when a trailer is hooked up.

If you installed the cable and connected the trailer and there was a short,
you will have blown that fuse.

If you wired your own harness, you still may have blown a fuse but it should
knock out the lamps on the vehicle as well. Check the continuity of the
trailers connector from each wire to the common ground. You should see bulb
resistance not a short and not an open.



"seniorgeezer" wrote in message
ups.com...
I have a 1999 Ford Ranger, and am in need of the electrical schematics
(wiring diagrams) so that I can troubleshooot a problem I have with a
four wire trailer lighting system.

The running lights work, but the turn signals, brake lights, and
flasher signals do not work.

Does anyone know where I can purchase the factory electrical wiring
manual for this Ford Ranger?

Thanks for any help,

Bob