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Microwave dead, no display or power

Rule out the outlet and breaker/GFCI first. Inside, the usual cause is a blown line (main) fuse, often blown on purpose by the monitor switch when a door switch fails, so test the door switches before replacing the fuse. Thermal cutoffs and the control board are next. Internal work is high voltage: trained techs only.

Cross-checked ~45 min advancedBrands: All

Before you start

  • DANGER: the high-voltage capacitor can hold a lethal charge even when unplugged
  • Inexperienced users should NOT open the cabinet
  • Trained techs: unplug, discharge the HV capacitor with an insulated tool and verify 0 V before any internal test

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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