No Power Reaching the Electric Brakes on a 1999 Travel Trailer  

Question:

Expert Reply:

The first step would be to determine if the wiring problem exists on the tow vehicle or with the trailer itself.

There are several ways to do this. If you have a friend or neighbor with a trailer that has electric brakes, you can try their trailer with your truck. Or conversely, you can try your trailer with their truck. You can also use a circuit tester like part # PTW2993 on the brake output pin of the trailer connector as a helper activates the manual brake switch on your brake controller. For a 6-way connector, the brake pin is either in the 9:00 position or in the center. For a 7-way connector, the brake pin is in the 5:00 location. Check the trailer connector on the vehicle, and clean or replace it if its corroded or damaged in any way.

If you have power on the brake pin with the manual brake controller switch activated, then the problem exists somewhere on your trailer. Make sure the connector on the trailer is not damaged. Trace the brake output circuit back to the brake magnet (typically the blue wire). Look for loose or broken connections and cracked or worn wire insulation. Examine the connections at each brake magnet. One lead from each magnet should ground to the trailer frame, the other lead connects to the brake circuit from the trailer connector.

If you do not have power at the brake pin, use a circuit tester on the blue wire exiting the rear of the controller. You should see voltage on this wire with the brakes applied or when the manual switch is applied. If you do not see voltage exiting the controller, check the black wire to ensure that voltage is reaching the controller. If there is voltage entering, but not exiting the controller, the controller is faulty and should be replaced.

I will link you to a brake controller troubleshooting FAQ article and video that you should find helpful.