Trailer Brakes Work when Brake Controller Switch is Used but Not when Brake Pedal is Applied

Expert Reply:

With the proportional controller you will not get full power to the brakes on the trailer when sitting still. You can test the output at the vehicle connector and you should get a few volts when sitting still. You will need to setup the controller, per manufacturer instructions, see link. Once you have the controller set up properly you will notice the trailer brakes when stopping especially when the stop is more abrupt.

If you hardwired the controller you may have connected the red wire to the wrong circuit. You will need to use a circuit tester, item # 3808 if you need one, to find the wire that goes hot when the brake pedal is pressed. This should not be a problem if you have a factory 7-Way connector and used the vehicle specific adapter for your vehicle, item # 20265.

instructions.asp?pn=N39510&manuf=DT

expert reply by: Amanda