Disaster Relief Vehicle

[KlutchInd]

That's pretty much what I ended up doing. Got a few things from etrailer and went at it. Used their #10 wire for hot lead and brake trigger. Under dash port gave me the brake signal to the controller. Had a controller from a previous truck and bought an adapter for plug in ease. The wires out back for lights were easy once I got them unwrapped. Ambulance company labels everything. Once I got it all wired up I found a blue and orange wire folded up in one of the looms which could be factory trailer wiring. But I had it all complete by that time.

 

[19Spec3]

I am installing a trailer hitch and 7-way wiring on my 2002 ERV -- can you share where you found the blue/orange wire? Much appreciated!!

 

[Bikersmurf]

I am installing a trailer hitch and 7-way wiring on my 2002 ERV -- can you share where you found the blue/orange wire? Much appreciated!!

I’d highly recommend a powered light module so the OEM wiring doesn’t have any extra load on them.
Uhaul asked me if I wanted them to wire it in... I said I’d likely have a better idea how to wire it in. He seemed somewhat insulted until I opened the door to the electric room(panel)... he stood wide eyed for a moment and then with a dumbfounded look said your right. It’d take us a day to figure out where to start. I had it all working in about 20 minutes after I got home.

The factory wiring doesn’t necessarily help out a lot. OEM Ford wiring shares a filament in the light for Turn signal and brakes. Ambulances, at least, have the brakes separated into a separate light again. To convert to a trailer takes a box to combine it again.