Over-the-range microwave mounted above a stainless electric range

Generic photo: Curtis Adams · Pexels License

Microwave light stays on (cooktop or cavity light)

Cooktop light: wrong bulb type or a light timer setting are common causes. Cavity light on with door closed points to a door switch not releasing or a stuck relay on the control board.

Single source ~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 5 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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