I was actually looking for an answer here.
Frigidaire microwave fan runs when door is closed.
In this case the microwave is indeed stuck in the on position even if nothing is actually being cooked.
Fridgidare microwave fmv152kma fan continues to run when door.
What you called the bottom door switch and the main relay lamp relay on the pcb to be closed.
A functioning door switch provides power to other components of the microwave and should interrupt power when the door is open.
The microwave works when cook time is entered but will not shut off until door is opened.
Fridgidare microwave fmv152kma fan continues to run when door is shut and cook time is completed.
Once the do read more.
No table movement no heat and no counter timing display.
The problem is the primary interlock switch is supposed to be open when the door is opened which would effectively remove the 120vac from the cooling fan.
The components that could stay on when the door is open but the door switch isn t working are the fan motor stirrer motor and interior light.
The only way for the fan motor to run is for both the primary interlock switch i e.
A malfunctioning circuit board may cause the control panel to run the light to turn on the fan to function and the turntable to rotate all signs that the microwave is working but the food may not be actually heating up.