cummins2014 wrote:
I agree its not a grounding issue, but it was worth pursuing, once I realized his lights work then its not the grounding, but we all kind of tried trouble shooting to try ,and help the OP , no need for criticism .
I am no expert ,but its simple wiring, and I have wired brakes, lights etc on trailers that I have fabricated ,and its not rocket science.
Not "criticizing", but I notice that everyone ALWAYS jumps on the "bad ground bandwagon" as the very first item to check and that has been pointed out multiple times muddying the waters.
Good troubleshooting requires how to break down the problem into smaller easier chunks.
Braking it down into two chunks helps greatly..
Chunk one, the truck.
Chunk number two, the trailer.
You can switch another truck into the picture with known good wiring and controller..
OR just pull the breakaway pin and drive forward..
ALL wheels should lock and slide.. No lock and slide then the issue is the trailer side..
Wheels lock and slide, then the issue is the TRUCK side..
Breakaway system bypasses the truck and controller and applies full on board battery voltage to the brake magnets causing the wheels to lock..
You now have cut your search area in half with one simple check.