Tekonsha Primus IQ Brake Controller Stops Working When Headlights Are Turned On

Question:

I installed the primus IQ control in a 2003 chev 1500 and it works perfect except when I turn on the head lights. With the headlights on, the screen is blank and controler does not work. As soon as the headlights are turned off the control will work.

asked by: Pat H

Expert Reply:

If the Tekonsha Primus IQ brake controller, part # TK90160 has been hardwired to your 2003 Chevrolet 1500 I would recommend checking, with a circuit tester like the Quickee tester, part # PTW2993, that the wires for the brake controller are connected to the correct wires under your dash.

The white wire is the ground wire and would need to be connected to the negative terminal of the vehicle battery. The black wire is the 12V power wire and would need to be connected to the positive battery terminal using a 20- or 30-amp circuit breaker. See the brake controller instructions for the correct size circuit breaker. The red wire needs to be connected to the stoplight switch circuit wire, behind the brake pedal, that will only have power when the brake pedal is pressed. The blue wire is for the electric brakes and will run from the brake controller to the back of the 7-Way connector on the rear of your vehicle.

If the Primus IQ brake controller is connected to your vehicle with a wire adapter, like the Tekonsha Wiring Harness, part # 3015-P, that plugs into the back of the brake controller and plugs into a factory brake controller port under the dash, I would unplug the adapter from the back of the brake controller and use the circuit tester to test the pins to make sure it is wired correctly.

I am including a link to the installation instructions on the Tekonsha Primus IQ brake controller, part # TK90160.

expert reply by: Jeff D