My Father in law has a 2006 Ford f250 and a 2004 cougar 5th wheel. He has had some problems with his brake controller/ brakes not working. He can take a 10 hour trip each way with no problems but then...
Brake controller is the built in ford one, I know that he has had the plug cleaned and is very carefull to seat the plug well. He is not sure if it is a wire short or the brake controller is bad. He has looked for any problems with the wires and found nothing. He is looking into buying an aftermarket brake controller and put it on to see if it works any different.