Trailer brake controller problems

[1993yj]

So here's the deal. My mom was driving my parents '03 Duramax the other day on the freeway when the brakes all of a sudden locked up for no reason. Took it in to where they bought it to be looked at, and had the ABS computer among other things replaced. Then left it at the shop for a while so the mechanic could check it out and make sure it was fixed. When they replaced everything they disconnected the trailer brake controller, and left it unhooked for a number of days, all the while the truck works fine. Today, the mechanic hooks up the controller again, and only gets 4 blocks before the brakes lock up again. So signs are obviously pointing to the brake controller. It is a Hoppy, pretty low end, not digital or anything. I have never heard of brake controllers causing this much of a problem before. Being pieces of sh*t and not working (ie. not actaully braking the trailer), yes. All of a sudden locking up all of the brakes in the truck, no. Anyone have any ideas or similar experiences? 98% sure that it is wired up correctly, since it has been used successfully in the past towing a Jeep on a Big Tex.

 

[1993yj]

No ideas or experiences? It just seems too weird to me that a controller failure would cause the brakes in the truck to lock up, assuming it is wired up correctly. If contollers did this when they failed, and accidents were caused, I would think that the manufacturers would be liable, and hopefully build their units so this wouldn't happen.

 

[Meat_]

My guess would be that it's wired wrong, somehow tied into the electrical part of the ABS. Doesn't Chev have a prewired set up for a trailer brake controler? Dodge does.

 

[1993yj]

My guess would be that it's wired wrong, somehow tied into the electrical part of the ABS.

My thoughts exactly, just can't figure it out.

Doesn't Chev have a prewired set up for a trailer brake controler? Dodge does.

I did my Dodge with the prewired tail it came with. Chevy has the same type of setup, only my parents truck didn't come with one as they got it used, so my dad ordered one and wired it up himself. The thing about the Chevys is that the instructions say to wire it up differently for an '03 and an '04.

Rather than going on about that and my theories of what the problem was, the shop replaced the brake booster and says that the problem is taken care of now, no relation to the brake controller. Thanks for the idea though Meat.