Brake Controller Turning On Brake Lights When Car is off and Draining Car Battery

Question:

Can you advise us as to whether the unit can be adjusted as it applies the brake lights even when parked in garage causing the battery to go flat and also cancels the cruise control on car even without a van on? . It has had this fault since it was fitted.

asked by: Derek T

Expert Reply:

It sounds like the unit was wired incorrectly. The white wire is a ground wire and should be connected to a suitable ground connection on the vehicle. The blue wire is the output wire that sends power to the trailer brakes when they need to be activated. The red wire should be connected to a stop light circuit. Typically, this is connected to one of the brake light switch wires at the top of your vehicle brake pedal. The black wire should be connected directly to the vehicle battery for a power source.

It seems like the red wire is connected to an incorrect wire as well as the blue wire. Use a circuit tester, like part # PTW2993, to find out what wires your brake controller is currently connected to, and which wires it should be connected to. I have also added a link to the instructions for this brake controller.

expert reply by: Patrick B

Nick H.

1/28/2020

Hi, I have had a Primus brake controller the past 9 years. I have noticed sever times recently it causes my car brake lights to stay on and battery go flat. Can controller be repaired or do I need to replace? Thanks nick

Jacob H.

1/29/2020

It sounds like you may have a wiring issue. The best thing to do would be to check to make sure all of your connections are still good. If your still having issues and cannot find the problem it may not be a bad idea to replace the brake controller with a new one. Start fresh and get rid of the headache. We have many different brake controllers to choose from so that you can pick whichever fits your application the best.

Helpful Links

dept-pg-Brake_Controller.aspx