Display shows dF and the refrigerator may be stuck in or out of defrost mode, with either warm temperatures or heavy frost.

Safety First: Unplug the refrigerator before accessing internal components.

Steps:

• Manual defrost: If heavy frost is present, manually defrost the evaporator by unplugging the unit and leaving doors open, or using a hair dryer on low.
• Check defrost sensor and heater: Access the evaporator area and test the defrost thermistor and heater for proper resistance and continuity.
• Inspect wiring: Verify that all defrost circuit connectors are secure and wires are not damaged.
• Control reset: After reassembly, restore power and see if the dF code clears. Some models allow a forced defrost test via button sequence; consult the service documentation if available.
• Replace PCB if needed: If all defrost components test good and wiring is intact, the main control board may need replacement.