LG Refrigerator Error Code F-sensor open

The F-sensor open code means the freezer compartment temperature sensor has an open circuit fault, and the control board is receiving no valid resistance signal from it. The board interprets this condition as a temperature reading below -50°C, which is outside the normal operating range. This prevents the refrigerator from accurately monitoring freezer temperatures. The cause is typically a failed thermistor, broken wiring, or a faulty connector.

Food safety depends on how long the error has been active and whether the freezer is still maintaining adequate cold temperatures. Without a functioning sensor, the refrigerator cannot properly regulate the freezer, so temperatures may rise over time. Check the actual freezer temperature with a thermometer and transfer perishables if the temperature has climbed above 0°F (-18°C). Address the fault as soon as possible to avoid further food spoilage risk.

If only the freezer temperature sensor needs replacement, parts typically cost in the range of $15 to $50 depending on the specific model. If a service technician is needed for diagnosis and installation, total repair costs including labor generally range from $100 to $250. Control board replacement, if required, would increase costs significantly above that range. Getting a diagnosis first helps avoid unnecessary parts replacement.

Start by unplugging the refrigerator and inspecting the freezer temperature sensor wiring harness and connector for visible damage, corrosion, or loose connections. Use a multimeter to check continuity in the wiring and measure resistance at the sensor terminals. If the sensor reads open circuit (infinite resistance), the thermistor needs to be replaced. If wiring and sensor test normal, the control board may need further evaluation.

A power reset may temporarily clear the error code from the display, but if the underlying fault in the sensor or wiring has not been repaired, the code will return once the control board performs its diagnostic checks again. A reset is useful for confirming whether the fault is intermittent, but it is not a substitute for diagnosing and repairing the open circuit condition.