Originally Posted by Les Clemetson
I did mean shoes. The tech that figured it out said it's an easy fix, you unbolt the whole plate behind the wheel that holds the solenoid and brake shoes and bolt a new one on.
When you unbolt the whole plate and replace it, you are not only replacing the shoes, but you are also replacing the magnet. (And as you said, it's easier for him and he makes more money selling you the whole thing vice just replacing the shoes.)
So I understand he may
have told you it was the shoes, but I believe your issue was a bad magnet. The shoes have nothing to do with the electrical side of your brakes. Your brake controller is only looking at the electrical circuit resistance/current flow. Your brake shoes won't affect that. When you plug in your trailer, without actually stepping on the brakes, the controller sends a very small current flow to the trailer; that's how it senses if there's a trailer attached. The brake shoes would not affect that small current flow.
Now, you may not be totally incorrect, in that the only way a shoe could "short out the system" is if it damaged the magnet; although it's still the magnet that's shorting, not the shoe. So, it may be the shoe caused
the magnet problem, but that's a failure mode I've never heard of, if it did.