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Microwave keypad not responding (or phantom presses)

Rule out control lock first. Then the usual causes are a worn or moisture-damaged membrane keypad or a loose ribbon at the control board. Unplugging the keypad ribbon separates a bad keypad from a bad board. The control board sits next to high-voltage parts on most models.

Cross-checked ~30 min moderateBrands: All

Before you start

  • DANGER: the high-voltage capacitor can hold a lethal charge even when unplugged
  • Inexperienced users should NOT open the control panel or cabinet
  • Trained techs: unplug, discharge and verify 0 V before reaching the control board

Diagnostic steps

Unlock all 4 steps with expected values

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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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Microwave keypad not responding (or phantom presses) · OnCall Tech