Microwave makes a loud buzzing or humming noise when running, louder than usual; may or may not heat.
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 the high-voltage section can indicate a serious fault. Avoid continued use.
User checks:
- 1. Confirm heating: Test with a cup of water for 30–60 seconds. If there is no heat and the noise is very loud, stop using the microwave.
- 2. Check for load: Never run the microwave empty; always have a load inside when testing.
- 3. Listen location: If the noise is clearly from the rear or side where the transformer sits, internal components are likely failing.
Because this involves high-voltage parts (transformer, diode, magnetron), diagnosis and repair must be done by a professional technician.
Repair Difficulty
Required Part
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