The door switch, often referred to as a primary interlock switch, provides power to the various components in the microwave when the door is in a closed position, and interrupts power when the door is open. This door switch is approximately 1 1/2 inches long, and has 2 metal prongs called terminals that extend from its body. Common sympto
...Read morems related to a faulty primary door switch include: microwave will not turn/shut off, or the microwave will not heat properly. You can check the switch for continuity using a multi-meter. With the actuator button depressed, you should see continuity between these terminals. If there is no continuity the switch will need to be replaced.
NOTE: Before you begin this repair, first make sure your microwave is unplugged, and that your capacitor is discharged. A capacitor stores large amounts of electricity even when your microwave is unplugged.
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