How to Test a Trailer Brake Controller on 2007 Ford Crown Victoria without Connecting to a Trailer

Updated 11/08/2019 | Published 11/07/2019

Products Featured in This Question

Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End

(154)

$12.43

Hook Probe Circuit Tester

(65)

$12.94

Question:

Hi! I recently purchased a Reese Towpower brake controller8508211 and I’m trying to hardwire it to my 2007 Ford Crown Victoria. The controller turns on but it is not sensing current coming from the cold side of my brake petal. When I manually apply the brakes it sends current out of the red wire stop light wire according to the manual. I tried simulating a stop light signal by running 12 volts to the red wire but the controller still won’t sense it. Is the controller faulty? Or will it only sense a stop light signal when connected to a trailer. Thank you for any help in advance.

asked by: Max

Expert Reply:

You don't need to be connected to a trailer to test a brake controller, but the brake controller does need to sense a slight amperage draw on the output circuit. You'll want to use a circuit tester like the # PTW2993 with one pin grounded and the other on the brake circuit output pin on your 7 way connection. Then you can hit the brake pedal of the vehicle and you should see the brake controller operate like normal. You'll need someone to help since it's hard to be at the rear of the vehicle and pressing the brake pedal.

If you don't have someone around to help you out with the process, you'll want to cut the blue wire behind the brake controller and then apply the manual override slider. Using your circuit tester, you'll want to make sure that you're getting voltage to the controller side of the cut wire when the manual override is activated. If the manual slide activates the trailer brake output wire properly, try the brake pedal. If the brake pedal activates the brake output properly also, then everything is working properly.

If there is power on the red wire before the brake pedal is pressed you have connected the red wire from the brake controller to the wrong circuit. You would then need to find the brake switch wire that has power ONLY when the brake pedal is activated. One thing to note-since the Towpower appears to be a proportional controller, you may have to test the trailer braking out in an empty parking lot in order to test to make sure it is functioning correctly once you've established that there is power.

If these connections check out and the brake controller is properly grounded then there is possibly a problem inside the brake controller.

I've also linked a helpful video for you that goes through the process of how to test a brake controller that you might want to refer back to during the testing process.

expert reply by: Erik B