I have a 28 xl and can not get power to the switch key when it does it will crank and run for a while and then go dead but it will crank and run a while. Now I can not get any power to switch at all I have checked all the fuses and they are good. the only fuse that does not have any power is the fifty amp next to the starter. I have power to the QGS controller and at the main fuse in the fuse box. Where do I need to look for the problem now