'97 F Super Duty Trailer Wiring

[tcartwri]

Yup, breakaway switch & battery on trailer.

On ours the power for the battery charger ran off the running light circuit. Therefor the lights had to be on for the battery to be charged. Yours is likely the same. If this is a commercial trailer, dot will ask you to demonstrate the functionality of the breakaway as part of their inspection.

We found the factory harness to be too small a gauge for our trailer, and bypassed it as well. We had three axles with brakes on them though.

 

[JJZ 109]

Ordeal finally solved. There was no wire (blue) from the brake controller (cab) end to the rear of the truck. The boys at a local shop did some rewiring for me. It should now be to industry standard and the truck should work with any trailer.
Combine that with the fact that the dealer installed an old junk controller and then I got 2 faulty units in a row from Auto Zone.
With a test light attached to the blue wire coming out of the AZ controller, the light would brighten and dim if you pivoted the controller in the mounting bracket. These were Hopkins units.
A trip the the local NAPA for another unit solved the problem. Plugged it in and it works fine. The kicker? It was a NAPA branded Hopkins unit, just a little lower budget model! :thumbsup: