How to use appliance service and diagnostic modes (general approach)

Most modern appliances have a service mode that shows stored codes, runs each load one at a time and displays sensor values. Entry sequences differ by model and are printed on the tech sheet. Use them to confirm a diagnosis before ordering parts.

Single source ~15 min easyBrands: All

Before you start

Component test modes energize motors, valves and heaters: keep hands clear and the cabinet closed where possible

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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