Trailer brakes stuck on 07 KW T600

My trailer brakes come on when ignition is in the ON position. The tractor brakes are NOT on. And all other lights work normally.

The brake pin at the rear of the sleeper is hot. So, the issue is in the tractor. I've swapped the relay to no avail.

Anyone had this issue? Have insight as to where to look?

Any help is appreciated.

 

Pulled relay and fuse. Still has power. Pulled trailer ABS relay. No power to brake lights. So, got a short somewhere. Now to find it.

 

I found the issue pretty quickly. It was at the plug on the rear of the sleeper. I guess it goes without saying that I've never had that one apart. Have a look.

 

Nope. All wires still where they needed to be. Just that rusted goop allowing current to cross over from the ABS post. I used a pick to break the connection and clean it out some. We'll enough to get by a dealership to pick up a new outlet (takes one with a large port for the huge ground wire) and make it home. Will clean it up and put the new one on tomorrow when the weather is nicer.