Tom,
First check for power at the transfer switch. If there is 120 volts coming into the transfer switch and no voltage on the output side, you have a bad transfer switch. However, if there is no voltage on the input side, you either have a problem in the cord or reel. If your coach has cord reel that rolls the cord onto a reel, they are prone to fail where the brushes make contact, but if your coach has a Glendinning locker style cord reel, the cord is hardwired to the coach so there are no brushes to fail and the reel can not be part of the problem.
Gerald