Using maker app diagnostics (LG Smart Diagnosis, Samsung Smart Care) before and during a service call

LG Smart Diagnosis plays fault data as tones from the appliance that the ThinQ app or LG support decodes, and Samsung Smart Care reads error codes into the app; connected Samsung units also push error notifications to SmartThings. These tools can give you a code and history before you arrive. They report basic faults only, so confirm every result with your own tests.

Cross-checked ~15 min easyBrands: LG, Samsung

Before you start

No panels are removed for app diagnostics.
Results are a starting point; live-voltage and component tests still follow their own safety rules.

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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