Usually the door interlock switches prevent the oven from turning on a) when the door is open and b) not until the control board starts it.
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The door interlock switches prevent the oven from turning on when the door is open and it shouldn’t operate until the control board starts it. So it appears that it may be a control board issue. Sticking relay contacts perhaps ''if'' the control board has relays on it of course
'''Be safety aware when working on a microwave'''. ''The voltage stored in the HV capacitor (>6000V DC) can cause serious injury and the capacitor needs to be correctly discharged before commencing any work inside the oven once the cover is removed. This voltage can be stored for months even if the oven has not been connected to the power for that length of time''
Hi @tumma ,
What is the model number of the microwave oven?
Usually the door interlock switches prevent the oven from turning on a) when the door is open and b) not until the control board starts it.
'''Be safety aware when working on a microwave'''. ''The voltage stored in the HV capacitor (>6000V DC) can cause serious injury and the capacitor needs to be correctly discharged before commencing any work inside the oven once the cover is removed. This voltage can be stored for months even if the oven has not been connected to the power for that length of time''