Hi, welcome to Just Answer. My name is ***** ***** I look forward to helping you! The electronic control, number 4 in the diagram at the link below, will likely need to be replaced. With the power surge, it would have been damaged and is what controls the fan power.
The link below is to the part you will need from a highly recommended company rated A+ with the Better Business Bureau. They offer a 100% money back guarantee, EVEN ON INSTALLED ELECTRICAL PARTS, for an entire year! They are the only company to allow returns on installed parts for a refund and offer a FULL ONE YEAR WARRANTY!
Access is gained by removing the grille from above the door. Once that is removed, there will be a screw visible at the top of the control panel. Remove that screw and lift the panel and it will hinge down, allowing full access for replacement of that control. Make sure the microwave is unplugged before any disassembly.
Please let me know if you have additional questions or need clarification. There is no additional charge for any follow up help!
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