Meile H 6400 Microwave

If the glass tray in your microwave doesn't turn, it may be due to a broken drive motor. Most units have a round glass turntable which has a motor driven coupler and roller guide turning the tray. To access the motor, first unplug the microwave and remove the bottom panel. The motor is usually held in place with a combination of retaining screws and wires. If the motor makes a grinding noise or won't rotate, it needs to be replaced. Use a multi-meter to test the motor terminals for continuity; if there is none the motor should be replaced. If the motor shows continuity but still isn't working, the microwave may need a live voltage test which should be performed by a qualified technician.

Coupler

If the glass tray in your microwave won't rotate, the issue may be with the drive coupler. Most microwave models have a round glass turntable which is powered by a motor driven coupler and roller guide. To check the coupler for damage, remove the tray and roller guide. If you need to remove the bottom cover to access the couple, unplug the microwave. Most units feature a three-sided coupler that easily detaches from the motor shaft; for others you may need to remove the motor first. Check the opening of the coupler that fits onto the motor shaft for cracks, wear, or damage.

Roller Guide

If the glass turntable in your microwave won't rotate, the issue may be with the roller guide, which lies under the glass tray and helps it to stay on track while rotating. The roller guide works with the coupler to rotate the turntable. Take out the glass tray in order to check the roller guide for cracks, wear, or damage. If the roller guide is worn, replace it.

Watch this video tutorial for fixing microwave issue for reference

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