Trailer brake problem?

PAThwacker wrote:
On my scenario my brakes were working and then not. Go down road and they worked. Still puzzled

Dollars to Doughnuts I would bet your problem and the OPs problems are one in the same..

Wiring.

Two major wiring trouble spots are the connections at each backing plate and the wires that are run inside the axle tube.

Frame manufacturer will run the wiring down one side of the frame to the first axle, splice in the backing plate, the wire inside the axle tube and a jumper to the next axle.

At the next axle they wire the jumper to the backing plate and the wire in the axle tube..

The wires in the axle tube are loose. Since they are loose they move around inside the tube which can rub the insulation off exposing the bare wire to the tube creating intermittent shorts or eventually breaking the strands of wire until you have no connection or shorted wires.

That can cause the controller to shut off the output causing no brakes condition depending on where the wire in the tube is at any given moment.

Investigate the connections at the backing plates, if in doubt about the condition of the connections, cut the splices and re do all of the connections.

Manufacturers typically do not use weatherproof splices, water gets in to the copper wire and over time the copper wire corrodes enough to no longer make a good electrical connection. And yes, copper wire does degrade with repeated or constant exposure to water/moisture. Moisture exposure with copper creates a oxide coating on the wire surface which does not conduct electricity very well..

If your axles have the wires running through the axles, cut all connections to those wires and run new wire outside the axle tubes to the backing plates on the other side. You can wire tie the wires to the tops of the axles or across the frame.