the turntable motor makes a loud grinding noise and sometimes just stops turning.

Diagnosis

The grinding noise and intermittent stoppage point to a failure in the turntable drive system. The plastic gearbox inside the tray motor commonly fails—its gears strip or seize. Alternatively, hardened food debris or a misaligned, cracked, or warped roller ring can jam the mechanism, causing the motor to strain and make noise.

How to Fix It

1. Unplug the microwave.
2. Remove the glass tray and the plastic roller ring underneath it.
3. Thoroughly clean the metal cavity floor and the channel where the roller ring sits, removing all debris.
4. Inspect the roller ring for cracks or warping. Ensure it rotates smoothly by hand on a flat surface.
5. Clean the guide pins on the underside of the glass tray. Reassemble the roller ring and glass tray, ensuring they are seated flat and level.
6. Plug in the microwave and test. The tray should rotate silently. If the noise persists, the motor is faulty.

If That Didn't Work

The turntable motor assembly needs replacement. After unplugging the unit, you must remove the internal oven cavity floor (typically held by screws under the roller ring channel) to access the motor mounted underneath. Disconnect its electrical connector, remove the mounting screws, and install the new motor (Samsung part #DD64-01232A is common for this model). Reassemble in reverse order.

Heads Up

Continuing to operate the microwave with a grinding, stalled motor can overload the main control board or the motor itself, leading to more expensive repairs. Always disconnect power before attempting any internal inspection or repair.