Troubleshooting No Trailer Brakes After Installing Reese Towpower Trailer Brake Controller
Updated 03/19/2018 | Published 03/16/2018
Question:
no brakes. just installed a Reese 8508700 controler have power and ground to unti power from brake light switch When hooked up to trailer LED is green Blue wire to trailer brakes flashes once then goes out Need help
asked by: Scott F
Helpful Expert Reply:
It sounds like you may have connected the red wire from your Reese Towpower Brake Controller to the wrong brake switch wire on the vehicle. I recommend verifying that the controller's red wire is connected to the cold side of the brake light switch, which is the wire that only receives power when the brake pedal is pressed, and no power with any other functions. I recommend using a circuit tester like # PTW2993 to test the wires.
If you can tell me the year, make, and model of your tow vehicle, I will be happy to see if I can find what color wire this might be. Please also let me know if this does not resolve the issue and we can continue to troubleshoot.
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