White countertop microwave on a kitchen counter
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Microwave keypad locked or in demo mode (keys dead, or runs but doesn't heat)

Two software modes cause many no-fault calls: control/child lock and demo (showroom) mode, which runs everything except the magnetron. Clear them with the model's key sequence before any high-voltage diagnosis.

Single source ~10 min easyBrands: Panasonic, GE, Whirlpool, Galanz, All

Before you start

  • No disassembly in this guide. If heating still fails after clearing modes, use the no-heat guide; HV work is caution.

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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Microwave keypad locked or in demo mode (keys dead, or runs but doesn't heat) · OnCall Tech