Microwave makes loud buzzing or humming noise while running, louder than normal, with reduced or no heating.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Loud buzzing from a microwave can indicate high-voltage arcing. Unplug the unit immediately and do not continue using it.
User checks:
- 1. Confirm noise source: Ensure the noise is from the microwave itself and not items inside (e.g., metal utensils, foil). Remove any suspect items and test briefly.
- 2. Check load: Never run the microwave empty; always test with a cup of water.
Technician-only: Inspect the transformer and magnetron for signs of overheating or arcing, tighten mounting bolts, and replace defective components as needed.
Repair Difficulty
Required Part
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