LG Refrigerator Error Code Er FS — Freezer Sensor Error
What this means
The Er FS error code indicates the freezer compartment temperature sensor (thermistor) is sending an abnormal reading to the control board. This sensor monitors the actual freezer temperature and tells the compressor when to run. If it fails, the freezer may run too cold, not cold enough, or cycle erratically.
Alternate codes: FS
Step-by-step fix
3 stepsLocate the freezer sensor
The freezer temperature sensor is typically located inside the freezer compartment, often clipped to the evaporator cover panel or mounted near the air vent. Check your model's service manual for the exact location.
Test the sensor
Unplug the refrigerator. Disconnect the sensor and test its resistance with a multimeter. At 0°F (-18°C), it should read approximately 16,000 ohms. At 40°F (4°C), approximately 7,500 ohms. Wildly different readings or 0/infinity indicates failure.
Compare the reading to a known-good temperature reading (use a separate thermometer to verify the ambient temperature around the sensor).
Replace the sensor
Remove the faulty sensor from its clip or mount. Install the new sensor in the same position. Reconnect the wiring and plug the refrigerator back in.
When to call a professional
If the sensor tests normal but the error persists, the main control board may not be reading the sensor input correctly. A technician can test the board's sensor circuit.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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