[plaidflannel]

My two-year-old, over-the-range GE microwave oven (model JVM1850SM3SS) today started humming constantly. I removed a very small food item as usual: opened door, light came on, humming stopped, closed door; then the humming started again. After several seconds, I unplugged the unit.

Ten minutes later, I plugged in the unit. The control panel displayed garbage, but would allow me to set the clock. During the time I was doing that, the humming continued. When I opened the door, the humming stopped, but the glass turntable was quite warm. I closed the door, the humming restarted, and after a few seconds, the unit powered off completely, as if a circuit breaker had tripped. The house breaker for the microwavehad NOT tripped.

What are the likely causes of the problem? The fixes? (I'm reasonably handy as a DIYer, and I know how to take the unit off the wall and then rehang it.)

I live in a rural area about 75 miles from the nearest town of any size. Independent appliance repair people typically charge $200 to $300 just to come and look at something. If this problem would require professional diagnosis and then additional travel, parts, and labor, I'm probably better off getting a new unit.