The Microwave Door Switch is an OEM replacement part for LG countertop microwaves. It monitors the door position electrically to prevent unsafe oven operation if ajar.  Symptoms of a bad door switch include: Inability to start or pause a cooking cycle unless securely latched   Error messages about the door being open Inconsistent detection of open/closed door positions Unreliable contact functioning after extended use Causes involve normal wear of electrical contacts and internals through many open/close uses. Exposure to moisture intrusion from spills may potentially damage sensitive switch circuitry over time as well. This genuine LG replacement switch is also compatible with Sears/Kenmore microwaves.This part fixes the following symptomsNo heatWon't startshuts off after a few seconds3B73362F (AP4437957) replaces 1325771, 3B73362E, 6600W1K003D, 6600W1K004C, 6600W1K004F, AH3522738, EA3522738, PS3522738.