White countertop microwave on a kitchen counter
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Microwave has display/clock but won't start

Rule out user settings first (control lock, demo mode, Start not pressed, shipping spacer). If those are fine, the control is not seeing a closed door or is not driving its relays: door switches, latch, or control board.

Cross-checked ~45 min moderateBrands: All

Before you start

  • DANGER: the HV capacitor can hold a lethal charge after the microwave is unplugged
  • Homeowners must not open the cabinet; internal steps are for trained techs only
  • Trained techs: unplug or breaker off, discharge the HV capacitor with an insulated tool, verify 0 V before touching internal parts
  • Never run the oven with the cabinet off or with interlocks bypassed

Diagnostic steps

Unlock all 6 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 has display/clock but won't start · OnCall Tech