Need Appliance Repair Help? Ask a Technician for Answers ASAP
There is a cavity thermal fuse up above the microwave. You would have to uninstall the microwave and remove the entire outer shell to see the dime sized thermal fuse mounted above the microwave cavity with 2 wires going to it. This thermal fuse cuts power to the microwave if something in the cavity catches on fire and makes the top of the cavity too hot. You'll need the full model number located on a sticker just inside the door way to look up the exact part number, but the part is usually about $20-30 or so.
We are on the honor system here. Please remember to rate my service by selecting a star at the top of the screen before you leave today. If you need anything else, just let me know. You can continue asking follow-up questions at no additional charge after rating my service if you still need assistance.