Michael for Model Number KHMS155LBL3 My wife was using the light and the fan and was cooking on the stove top last night. She went to start the microwave to cook a vegetable, and got a “poof” sound and the unit shutdown. I unplugged the unit and then reset the circuit breaker. The breaker did not seem tripped however. I then plugged it back in and the fan started running. Now the fan runs continuously and can only be stopped by unplugging the microwave. It is unresponsive to the key pad. Other aspects seem to function normally and we did run it to cook the vegetable for a few minutes. I also checked for exhaust obstructions and found none. I know the unit has some sensor for heat and turns on the fan to protect the microwave from excessive heat. However there was no reason for it to have gone into this state as best I can tell. I unplugged it last night and when re-plugging it in this morning the fan starts right up. Appreciate clues as to where to start with this problem.
Answer Hello Michael. You need to check the door switches on the unit. You can test this with a multi-meter TJMA-DMT3. Here is a link on how to use a multi-meter. http://forum.appliancepartspros.com/oven-repair-including-ranges-cooktops/4810-how-check-continuity-ohmmeter.html Read More... Answered by AppliancePartsPros.com | Monday, September 8, 2014