Yes loose wires have been reported a few times. Enough that I would certainly look there first. You may also check the outlet that the microwave is plugged in to. It's somewhat accessible from the outside trash can door. Be safe and make sure you're not plugged in to shore power or have the generator running when you do this. I have my rig covered for the winter otherwise I'd go in to see how to acces the back of the breaker panel. If I had to guess though - I would think the breaker panel trim cover comes off from the front to access the breakers. May be held on with screws or just some simple spring clips. Let us know you're findings! Good luck.
