The Motor-Turn is an OEM part compatible with Whirlpool microwaves. Located inside the microwave cavity on the turntable mechanism, the motor-turn contains the turntable motor and drive components.  Causes of a bad motor-turn can include a faulty motor, worn gears or pulleys, or broken turntable shaft.  Symptoms of a bad motor-turn include: The turntable not rotating or rotating unevenly Loud grinding noises emanating from inside the cavity Burning or uneven cooking of foods Traces of sparks near the turntable mechanism This OEM Whirlpool replacement motor-turn assembly is also compatible with Maytag, KitchenAid, Jenn-Air, Amana, Magic Chef, Admiral, Norge, Roper, and some Kenmore microwaves.W11661547 (AP7211120) replaces W10143959, W10466421, 8206102, W10286824.