Sensor cook / auto programs not working

Sensor programs depend on a humidity or vapor sensor and a correct load. Most failures are usage (tight covers, tiny loads, hot cavity) or grease on the sensor; a failed sensor or wiring shows a code.

Cross-checked ~30 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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