Agrivated, looks like the fuse 18amp is in the back on top. You will have to remove the shell off the microwave to get at it. This one operates with a inverter..you have some high voltage there. Make sure it's unplugged. While you have it apart, check the primary switch, top one on door latch. If the monitor switch finds this closed when the door is opened it will blow that fuse. You also have a cavity thermal cut out that will shut the oven down. Catriver...post back.
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