When I turn on my stove the heat obviously rises to the microwave hood fan combo. As soon as the microwave hood fan starts to heat up, the display disappears, and the microwave hood fan starts beeping. The exhaust fan that is supposed to come on when there is too much heat from the stove, does not activate. The microwave hood fan continues to beep until the hood fan cools off, then the display comes on again, and the unit functions again. It's almost like the heat causes the power to shut down. When I removed the grease screens, I saw that there was a "synchronous motor" inside. Is this part maybe screwed up, or could it be the computer portion that is fried?