We have a 15 year old GE Spacemaker microwave that is built in under the cabinet above the stove. We had a brief power outage that zapped it. Even after I flipped the circuit breaker nothing at all shows on the display panel. Verified that the socket is good by plugging something else into it and verified that it is the microwave by plugging it into another outlet. The owner's manual is no help and GE website just says to make a service appointment. Is there an internal fuse or something that can be checked. Any suggestions?