[Kevmarjax]

Microwave is less than 2 years old. When you try to start any cooking function it completely goes dead, including all lights and control panel, for about 2 seconds, then comes back on and the control panel indicates you should check the food because there was a power outage. I tried plugging the unit into an different outlet on a different circuit but it did the same thing. It appears to be tripping some internal automatic resetting fuse? The unit worked fine before and has never had any previous problems. Any ideas on what might be wrong? Vent fan and surface light functions work fine.

[Kevmarjax]

I tried starting the microwave a couple more times and it finally went completely dead. The unit had no power to anything. I removed it from the wall, pulled the cabinet and under the control panel was a tech sheet with a diagnosis tree. I followed the diagnosis tree steps to the overheat thermostat on the Magnatron tube. The thermostat tested with a multimeter as open and it should be normally closed. I temporarily jumped the thermostat to see if the control panel powered up and it did. I assume the contacts on the normally closed thermostat failed. I ordered a new thermostat, so I will be able to confirm the diagnosis when the new thermostat is installed.