The Door Switch is an OEM part for Frigidaire microwaves, designed to ensure the appliance operates safely by signaling when the door is securely closed. This switch is critical for preventing the microwave from running if the door is open, a key safety feature that protects users from exposure to microwave radiation. Causes of a bad Door Switch can include mechanical failure due to normal wear and tear from repeated opening and closing of the microwave door.  Symptoms of a bad Door Switch include: The microwave not starting or heating when the door is closed. The appliance continuing to operate when the door is opened. Intermittent operation or sudden stopping during use. Displaying error messages related to the door or switches. This OEM Frigidaire part is also compatible with Electrolux, Gibson, Kelvinator and some Kenmore models.5304509459 (AP6230614) replaces 5304464098, 4583655, PS12071302.