Bauknecht High-Voltage Component Short or Magnetron Failure

Microwave runs but makes loud buzzing or humming noise, louder than normal, with poor or no heating.

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

Shorted high-voltage diode, Failing magnetron, Partially shorted high-voltage transformer, Arcing in waveguide

Critical safety warning: Loud buzzing from the high-voltage section indicates a potentially dangerous fault. Unplug immediately.

Step 1 – Stop using the appliance: Continued operation can cause further damage or fire.
Step 2 – Visual cavity check: Inspect the interior for burn marks, especially near the waveguide cover (mica plate). Replace a burnt or damaged waveguide cover.
Step 3 – Professional diagnosis: A technician should test the HV diode, capacitor, transformer, and magnetron, and inspect the waveguide for arcing damage.

Professional Required 5/5

High-Voltage Transformer

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