Unit was painted inside recently, but apparently some paint fumes still lingered so that when the unit was turn on, there was a very small explosion that took out the flam sensor thermostat. This thermostat interrupts the white leg of the AC input and cuts off all power.Performing a continuity test on the flame sensor showed it was permanently open (no continuity). Turns out I had a similar part from an old coffee maker and when I installed this part, the microwave turned on just fine. So I order the correct sensor from Parts Select. Part installation involved removing the TT20 Security Star bits (4) and the right/left side phillips screws. Now the top/side unit cover comes off by pulling the cover backwards and up and out. The flame sensor is in the middle of the front section underneath the top cover, and comes out easily with pull-off connectors. There are also bendable pins that hold the sensor down flush to the top of the unit.
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