I have a 1988 winnebago 33ru cheiftain. I was wondering if anyone could tell me where to start to track down the promblem. When I am plugged in everything works. But when I am not plugged into 30amp I have nothing. When I turn on my ignition but dont start the engine and have my battery switch on aux i have 12v. I started my gennerator and I didnt even have 110 then. Any ideas