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Trailer Brake Controller Not Sending Signal (2013 Ford Expedition)

We just bought a 2013 Casita 17’ camping trailer, which has Dexter electric brakes. The OEM brake controller in the Expy recognizes the trailer, and the electronic gain adjustment seems to work. But it does not actuate the brakes. I checked the terminal on the 7-wire connector, and the blue wire that feeds that terminal, and there is no current when we press the brake pedal. So the problem would appear to be with the Expy and not with the trailer.

I am not getting an error message on the Information Display, which the manual says I should if there is an interrupt or short. I checked the 30A fuse for the line and it looks OK, as does the fuse for the controller. So what’s the problem?

The previous owner never used the electric brakes; he was actually unaware the trailer had them. The Casita is light enough that he could tow it with a Nissan Frontier V6 pickup. I was worried that the drums might be rusted and/or the brakes inoperative after not being used for three years, but I took a wheel off and adjusted one, and it would adjust to the point where I couldn’t turn the drum; then I backed it off a little. Besides, there’s no current at the terminal on the Expy!

I’m stuck. Any ideas?

/Mr Lynn

Trailer wiring is an ever failing syndrome, but you have to start at step 1, is there voltage going to the brakes, if yes, step 2 do the brakes operate, if no brakes are the problem.

There is not really much that can be wrong. Don’t assume that the wiring plug on the trailer is wired correctly. I have seen this countless times on trailers that I have pulled. After checking for voltage on the truck side of the equation, go to the trailer plug and check that it is properly wired.

On my farm trailers, I always have the issue with brush catching the wires and ripping them loose. There should be 2 wires on each brake drum from which one of them is ground and one is wired to the brake controller. It is also likely that you have a brake away controller mounted on your tongue. This is a simple switch and small battery that will engage the brakes in the unfortunate event your trailer comes loose while cruising down the road. Check for power here when the brakes are depressed and check that they have good connection. Inside the drum is a electromagnet that engages the brakes. It is possible that the shoes are out of adjustment or you have a bad electromagnet.

Electric trailer brakes? On Car Talk? OMG!! … lol …