My maytag (MSD2757AEB) refrigerator started having problems a few weeks ago. It cannot defrost anymore. I've vacuumed and manually defrosted it 2x since then. I've tried hitting the test and L1 on the controller but got a buzzing sound from the controller rather than a single audible click (which is what I was expecting). I measure about 25V across the thermostat when that happens. The thermostat impedance seems ~250kOhms and the heater is not open. I am suspect of the thermostat though with the 25V across it. At this point I am not sure if it is the controller or the thermostat/heater (since they are sold as a unit). But I have pretty much ruled out the fans, motors, seals, compressor problem, etc. Any thoughts?
Thanks