I have a 2009 f250 diesel with onboard TBC. When towing my 5th wheel i get no trailer braking when the brake pedal is applied. When I use the manual slide the trailer brakes work fine and I get a gain display in the control panel display. I get no indicator when using the brake pedal. I checked all fuses and all are good both under the hood and in the kick panel. The trailer is new 2013 and the truck has 16000 miles. All connectors at the trailer plug appears new and without any issues. I am baffled yet when searching the net see others with the same problem and other than a fuse or bad connector no real answers. Help.