Microwave makes loud buzzing or humming noise during operation, louder than usual, sometimes accompanied by a burning smell.
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: Immediately stop the microwave and unplug it if you hear unusually loud buzzing or smell burning.
User-level checks:
- Inspect the interior cavity and waveguide cover for burn marks or arcing spots.
- Clean any food splatters or grease thoroughly.
Do not continue to operate the microwave if the noise persists, as this can cause further damage.
Technician-level:
- Check the high-voltage circuit (transformer/inverter, diode, capacitor, magnetron) for shorts or overheating.
- Replace the defective component and any burned waveguide cover.
This repair involves high voltage and should only be performed by a qualified technician.
Repair Difficulty
Required Part
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