Troubleshooting Draw-Tite Activator IV Brake Controller Installation

Published 11/02/2019

Question:

the only brake working is the manual slide control

asked by: John N

Expert Reply:

If the trailer brakes are working with the manual brake slider switch, but not with the vehicle brakes, then the contorller isn't getting a signal in on the red wire.

Use a circuit tester like # PTW2993 and probe that red wire as you use manual brake slider. If you are getting signal on that wire, then the controller is faulty. If you aren't getting power on that wire, you'll want to review the installation procedure. That red wire should be connected to the brake stop lamp switch. If your vehicle has a tow package and you had a plug and play installation, make sure you're using the correct wiring harness. If the controller was hardwired, be sure you've tapped that red wire into the correct circuit. The stop light switch is usually located at the top of the brake pedal. Use the circuit tester to check the wires exiting the switch, there could be several. The red brake controller wire should be tapped into the circuit that only shows power with the brake pedal pressed.

If you'd care to reply with a description of the year, make and model of vehicle, I might have some more specific things to check. I've linked you to a help article with more troubleshooting advice.

expert reply by: Mike L