Originally Posted by 3 Squids (Post 232393)

Found the problem. The blue wire in the factory harness is grounding out somewhere between both ends. According to the FSM it doesn't have any splices in it just a plug at the firewall harness. I cut the blue wire coming out of the control box and connected a long jumper wire to it then ran the jumper wire straight to the trailer and sure enough the brakes work fine. So for a quick fix I ran the jumper along the frame to the back of the receiver plug and all is normal now.