I have an F250 2012, TCB is factory installed. With a gooseneck trailer fully connected, all lights work, the truck still shows that the trailer is disconnected. If I move the truck and trailer and apply the brakes the trailer brakes instantly lock up. All the fuses are good. I have even replaced the connector on the trailer. I have also hooked up my 4 wire trailer plug, truck still says trailer not connected. Obviously electrical issues are not my strong point. Any ideas?