Main electrical panel beside a subpanel with its cover removed

Samsung refrigerators: reading display codes, Cooling Off (demo) mode, and forced defrost (Fd) / test mode concepts

Samsung asks owners not to unplug or press buttons to make a code go away, because that erases what the technician needs; only a few power-related codes are cleared by a 60-second power cut. An OF OF or similar display is Cooling Off (demo) mode, not a fault. The test mode is entered by holding a model-specific pair of buttons until the display blanks, then pressing a button to step through modes, one of which is forced defrost (Fd).

Cross-checked ~45 min moderateBrands: Samsung

Before you start

Forced defrost and test modes are control-only; do not open the sealed system
Sealed-system diagnosis (compressor, leaks, recharge) is blocked: refer to an EPA 608-certified technician
Unplug before removing the evaporator cover or any panel

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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