Trailer Brakes Work with Break Away System But Not with Brake Controller
Question:
Adjusted brakes and when I depress vehicle brake or controller only get humming from brake area no braking. Pulled the safety plunger and the brakes locked up. Not sure how to proceed. Measured voltage to brakes and have power to the hubs.
asked by: Bill G
Expert Reply:
It sounds like the brake controller might need to be reset or the wiring from the vehicle side to the breakaway system needs to be examined. Try adjusting the power output of the controller. If that does not work, you can test the controller itself using a circuit tester like # PTW2993 if needed.
Sever the blue wire a few inches from the back of the controller and use the circuit tester to test the end coming from the controller while applying the manual override. If it does not show power, then there is something wrong with the controller and it will need to be replaced.
If it shows power do the same test after reconnecting the blue wire only this time test the output pin on the trailer connector. If the power is making it to that point, then the issue must be on the trailer. The output to the trailer brakes should go first to the breakaway system and then to the brakes. Check the breakaway system ground and the magnet grounds to make sure everything is attached to a bare metal surface.
For the sake of testing, you can connect a magnet directly to the brake output circuit on the trailer side connector to bypass the breakaway system. If it works with the controller like it is supposed to then you know the issue is with the breakaway system or its wiring.
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on Trailer Breakaway Kit
Lee W.
4/21/2024
I have the same issue. After installing new brakes and a new breakway system, the brakes work fine with the breakaway power engaged, but when the same brake wires are receiving power from the vehicle (0-12v depending on brake pressure/gain of course) they do not work (!?). I tested and see 12v going to the brakes in both cases. Potenally(?) related is that I am not seeing power on the red aux power wire...