I know the older Ford TBCs were always checking the electrical integrity of the trailer brakes, so if you developed a short either in the wiring or thru a worn magnet it would throw a code.
With that being said, they were overly sensitive and tended to show a lot of faults that weren't there. I think Ford has overcome the oversensitivity, but as you found- the TBC does look for complete circuit to & from the brakes.
When you do reconnect the brakes it is very important that a ground wire be ran to the trailer 7 way. Don't just attach one end of the magnet wire to the frame.
You should also wire in a battery and breakaway switch, as most states (check to be sure- your state might not) require a trailer with brakes to be able to stop on it's own if a breakaway occurs, and in the case of electric brakes you have to have a battery.
With that being said, they were overly sensitive and tended to show a lot of faults that weren't there. I think Ford has overcome the oversensitivity, but as you found- the TBC does look for complete circuit to & from the brakes.
When you do reconnect the brakes it is very important that a ground wire be ran to the trailer 7 way. Don't just attach one end of the magnet wire to the frame.
You should also wire in a battery and breakaway switch, as most states (check to be sure- your state might not) require a trailer with brakes to be able to stop on it's own if a breakaway occurs, and in the case of electric brakes you have to have a battery.
