Microwave makes loud buzzing or humming noise when running, louder than usual, 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: High-voltage components are dangerous. Do not open the cabinet unless you are trained.
User checks:
- Stop the microwave immediately if you hear unusually loud buzzing.
- Check for any burning smell; if present, keep the unit unplugged.
- Confirm that the noise occurs only when cooking (not when just opening/closing the door).
Because this symptom is typically caused by HV components, a professional should inspect and replace the transformer, magnetron, or capacitor as needed.
Repair Difficulty
Required Part
We may earn a commission from links on this page.