i have post this problem before about my microwave not working, this is what i have done new breaker and receptacle, i have power on the wires that go into receptacle but when i plug into it nothing ...
Our microwave was just replaced under warranty by FR. It worked fine and then it didn't, but the last use it got very hot. DH shut off the circuit until we could get home and check it out. If you do need to replace yours, be aware that the vented trim pieces don't fit all microwaves. Both of ours were Magic Chef, but they had to include a new trim piece.
Good testing idea above. Any chance yours is still under warranty????