High Voltage Diode

We pulled the unit out of the wall, removed the metal shroud by removing the screws, discharged the capacitor with a set of insulated long nose pliers. I replaced the magnetron and diode. The magnetron is just 4 screws and a couple plugs. On the magnetron you also need to remove the temp sensor that is screwed to it and put it on the n ... Read more ew magnetron. The diode is connected to the capacitor and connected to the frame with a screw. Just unscrew and replace. This did not fix our problem though. It still did not heat so I decided to replace the fuse and door switches. When I pulled the door switches, one of the switches, which as a little button on the top that gets pushed in by the door, was stuck down. I replaced it and that fixed it. So $400 for $20 fix...lesson learned. Check the fuse and door switches first if your microwave stops heating.

Removed outside cover (more than a dozen screws) including top-rear plate and 120V cable strain relief. Swung control panel aside (one screw at top, then lift, pull, and tilt down). Removed inner magnetron volume cover, about a dozen more screws in truly random-seeming locations, and swung aside leaving cables connected. Loosen top-side ... Read more plastic duct work (about 3 screws) to access magnetron nuts and bottom-side plastic duct work (about 2 more screws and a clip to provide clearance for magnetron removal). Disconnect thermostat (2 screws) and power cable to magnetron. Used small socket wrench for 4 nuts to release magnetron and bracket. Changed bracket to new magnetron (2 screws). Replaced magnetron and diode, reassembled everything. Unit seems perfectly functional now. If I were doing it again I'd take pictures so I'd know where all the screws came from.

I had to pull the unit from the wall by removing all of the mounting screws. Also removed the front panel of the unit to expose all of the parts. That was the longest part of the repair. The rest; replacing part by part was easy. The only thing that held up the progress was the polarity of the thermostat. I either guessed right, or it ... Read more didn't matter. Once all of the parts were replaced, I powered up the unit, put a glass of water in the microwave to make sure it worked. Then I reinstalled the unit in its original spot and replaced all of the mounting screws, front key panel. It was a good hour in total, most of that removing and reinstalling the unit above the stove.