There should be a fuse on the circuit board. We had to replace one in our micro several years ago. We recently had the door handle break off our GE micro convection. We ended up replacing it with a Furrion convection micro. Ours was mounted to a welded steel frame. I had to put a spacer behind the frame and add a piece of plywood across a section of the frame to get the new micro mounting bolts to to line up. Other than that, the installation was pretty straight forward. We looked all over for an oven that had the same mounting bolt spacing as the GE without success. It was especially fun during China virus.
2002 Tradewinds LTC Founders Ed
2004 Tundra Double Cab toad, 2007 Honda Goldwing