I noticed last night that my backup lights are not working. I removed the taillight assembly and swapped the backup bulb to the brake socket and it worked so I know it is not an issue with the bulb.

Tried to find a fuse for the backup lights but based on the fuse diagrams I found online (the one on the fuse box cover is unreadable) there is no fuse for them. I put a multi meter on the socket and it does not seem to be getting power. This assumption is supported by the fact that the bulb worked in the brake socket.

I remember reading somewhere (can't remember where at the moment) something about a back up (light?) switch somewhere on the transmission? could this be the culprit? (I have the manual transmission) Where is it located and how would I troubleshoot to see if it is the issue?

 

I decided to replace the backup light switch on the transmission and discoverd that there is nothing connected to it. It appears that the wiring that goes between it and the taillight wiring harness is gone from the truck.

Called my local Ford dealer, they can't get it anymore and an online search of the part number gets no results.

Does anyone know where you can get wiring harness' for these trucks?

 

Wouldn't be rocket science to just wire them up. Probably hours of entertainment though. There is likely some trace of the old wire somewhere, and you could extent that, if you could identify it. You might even find it tucked inside a cross member or something. Or you could just run a fused hot to one side of the switch and run a wire the from other terminal from there to either of the backup lights, they should at least still be tied together at the rear.