Troubleshooting Factory Brake Controller in 2013 Ford Expedition EL That Does Not Detect Trailer

Updated 06/20/2018 | Published 06/18/2018

Products Featured in This Question

Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional

(2763)

$160.71

Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers - Ford

(348)

$19.86

Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional

(6648)

$169.94

Hook Probe Circuit Tester

(60)

$12.41

Question:

The Trailer Brake Controller is not recognizing a trailer on my 2013 Expedition EL. When i plug in my trailer, my Expedition dash says No Trailer. I have checked all of the fuses under the hood and in the cab of the Expedition. When I plug in the trailer, the running lights work, both turn signals work, and the brake lights work. But the electric brakes do not work. I connected one of my neighbors truck to the trailer the the trailer break works. I have confirmed the trailer brake controller is getting power in, but not sure if the trailer brake controller is sending power out to the trailer. Is there a way to test the trailer brake controller. Are the trailer brake controller in Ford Expedition famous for being bad? How can I get my trailer brake controller to work?

asked by: Todd J

Expert Reply:

Your brake controller's "no trailer connected" error message indicates an issue on the brake circuit. Your lights can all work fine since they are on separate circuits, but that error message tells you that the wire/circuit for the trailer brakes has a fault such as a loose connection, a short, a faulty controller or that the trailer plug, or vehicle socket have a corrosion problem on the contacts for the brake circuit. The linked photo shows you which contacts on the trailer plug relate to the brake circuit and ground.

If you have a circuit tester like # PTW2993 apply it to the ground and brake circuit contacts on the vehicle socket while a helper activates the manual over-ride on the controller with it set to full power. You should detect voltage on the brake circuit pin. If so, focus on the trailer since the issue is likely to be there. Trace all trailer brake wiring from the plug to each brake, looking for worn insulation or wire rubbing on the trailer frame.

If you do not get a brake signal on the 7-way socket, then move to the passenger compartment and test the blue wire at the back of the controller. You will need to cut it a few inches from the controller, leaving enough wire to re-splice it after testing. Repeat the manual override test. If you get a signal at the back of the controller, then you know the problem is somewhere in the vehicle wiring between the controller and the 7-way. Additional steps you can take are detailed in the linked articles.

Factory-installed trailer brake controllers can be appealing since their installation typically offers nicer cosmetics, but many drivers who have one still ultimately replace them with an aftermarket unit that tends to work a lot better and that is more reliable long-term. Among the most popular aftermarket controllers are the Prodigy P2 # 90885 and the P3 # 90195, both of which install in your Expedition using wiring adapter part # 3034-P that connects under the dash as shown in the linked video.