I am a licensed electronic technician with 30+ years experience. I recently had a GE over the range microwave fail..no power. It is plugged into a dedicated outlet. Model JVM3160FS3SS.
I opened the unit to discover a blown main fuse. This is a 20 Amp fast-blow standard glass fuse. A search for a replacement fuse at the GE parts website was startling!
All parts for this microwave are priced out of this world. The fuse costs 50+ dollars for one piece, whereas general electronic suppliers sell these in 5-packs for under 10 dollars. GE won’t even sell you the magnetron tube, but third party sellers will for 260+ dollars. Heck, the replacement fan motor will cost you 340+ dollars.
The lesson here: This microwave is not economically repairable. A new unit with 1 year warranty sells for $199.