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Appliance Error Codes

What Does FS Error Mean on LG LRSXS26366S?

Error FS on LG LRSXS26366S: Freezer temperature sensor short circuit or open circuit — freezer thermistor ma. Follow the troubleshooting steps below to diagnose and fix this refrigerator issue. The FS error code on your LG LRSXS26366S refrigerator indicates the main freezer temperature sensor (thermistor) has a short or open circuit fault. The freezer thermistor is the primary temperature feedback sensor for the freezer compartment — the control board uses its reading to regulate compressor cycling and defrost timing. FS is a straightforward repair requiring thermistor replacement. ## What Does FS Mean? The FS error appears when the LRSXS26366S control board detects an abnormal resistance from the main freezer temperature sensor. Like all NTC thermistors, the freezer sensor changes resistance with temperature — higher resistance at lower temperatures, lower resistance at higher temperatures. A reading far above or below the expected range triggers FS. LG displays the code as EFS or E FS on some models. The freezer sensor is distinct from the defrost sensor (dS) — the freezer sensor monitors ambient compartment temperature continuously, while the defrost sensor specifically monitors evaporator coil temperature during defrost cycles. Without a functioning freezer sensor, the control board operates the compressor on a default or safety schedule, which may not maintain accurate temperatures. Food safety in the freezer may be compromised if FS is not resolved promptly. ## Possible Causes 1. Failed freezer thermistor with an open circuit from thermal cycling — the most common cause 2. Failed freezer thermistor with a short circuit from moisture or physical damage 3. Loose or corroded connector between the sensor and the control board 4. Broken wire in the sensor harness from vibration fatigue 5. Failed main control board sensor input circuit ## Troubleshooting Steps | Step | Action | Expected Result | |------|--------|-----------------| | 1 | Remove all food from the freezer and unplug the LRSXS26366S | Freezer is empty and unplugged | | 2 | Locate the freezer temperature sensor — typically a small probe mounted on a clip inside the freezer compartment, usually near the top rear corner or on the evaporator cover | Freezer thermistor is located | | 3 | Disconnect the sensor’s 2-wire connector and measure resistance at room temperature with a multimeter; at 77°F (25°C) a typical LG freezer thermistor reads approximately 5,000 to 15,000 ohms; OL confirms open circuit; near zero confirms short | Sensor resistance is measured and compared to specification | | 4 | Replace the thermistor if resistance is outside the normal range; note the clip or mounting method and duplicate it with the replacement sensor | New thermistor is installed in the correct position | | 5 | Reconnect wiring, restore power, and allow the freezer to cool to its set temperature (approximately 0°F / -18°C) over 4 to 6 hours; verify FS has cleared from the display | FS does not return and freezer reaches set temperature | Food that has warmed above 0°F while FS is active may have partially thawed. Check food quality before refreezing. Partially thawed food that still has ice crystals can generally be safely refrozen, but quality may be affected. ## When to Call a Technician Contact LG authorized service if: - The thermistor replacement did not resolve FS — the control board sensor input has failed

  • FS appears together with rS (refrigerator sensor error) — multiple sensor failures may indicate a harness or control board issue Professional repair costs for FS issues typically range from $60 to $200 depending on the specific component and your service region. ## Frequently Asked Questions ### Does FS mean my LG freezer will stop freezing? FS means the control board cannot accurately read the freezer temperature. The compressor may continue to operate on a default cycle, so the freezer may remain cold, but the temperature control will be imprecise. Some LG models enter a protective mode that runs the compressor more frequently when FS is active. Check food temperatures directly with a thermometer rather than relying on the display.

Can I use a universal thermistor to replace the LG freezer sensor? No. LG thermistors have specific resistance-temperature curves calibrated to the control board’s software. A universal thermistor with a different curve will produce incorrect temperature readings even if the physical connector is compatible. Always use the correct OEM or equivalent part number for your specific LG refrigerator model.

Section titled “Can I use a universal thermistor to replace the LG freezer sensor? No. LG thermistors have specific resistance-temperature curves calibrated to the control board’s software. A universal thermistor with a different curve will produce incorrect temperature readings even if the physical connector is compatible. Always use the correct OEM or equivalent part number for your specific LG refrigerator model.”

Why do both FS and rF show at the same time on my LG refrigerator? FS (freezer sensor error) and rF (refrigerator fan error) appearing simultaneously suggests the refrigerator has significant frost accumulation that is both blocking the fan (causing rF) and causing the thermistor to read abnormally (causing FS). Perform a complete manual defrost first — in many cases both codes clear after a thorough defrost. If FS persists after defrosting when rF has cleared, replace the freezer thermistor.

Section titled “Why do both FS and rF show at the same time on my LG refrigerator? FS (freezer sensor error) and rF (refrigerator fan error) appearing simultaneously suggests the refrigerator has significant frost accumulation that is both blocking the fan (causing rF) and causing the thermistor to read abnormally (causing FS). Perform a complete manual defrost first — in many cases both codes clear after a thorough defrost. If FS persists after defrosting when rF has cleared, replace the freezer thermistor.”

How do I know if my LG refrigerator is maintaining the correct temperature when FS is active? Place a separate digital thermometer in the freezer compartment to monitor actual temperature independently of the control panel display. A properly functioning freezer should maintain 0°F (-18°C) or below. If the thermometer reading deviates significantly from 0°F, the compressor cycle is not compensating correctly for the missing sensor signal and food safety is at risk. Reference: LG official support documentation (lg.com/us/support) and authorized service guides ### Is it safe to keep using my LG LRSXS26366S with error FS? If error FS does not indicate an immediate safety hazard such as a gas leak, electrical short, or water flooding, you can continue limited use while monitoring the appliance. However, running the refrigerator with an active error code increases the risk of further damage. Address the underlying issue as soon as possible. For high-severity errors, disconnect the appliance and contact a qualified technician. ### How much does it cost to fix error FS on a LG LRSXS26366S? Repair costs for error FS on the LG LRSXS26366S refrigerator depend on the root cause. DIY fixes such as cleaning filters, resetting the unit, or reconnecting loose wires cost nothing beyond basic tools. If a component replacement is needed, parts and labor from a certified technician are the main expenses. Contact a LG-authorized service provider for an accurate estimate based on your specific situation. ### What does error code FS mean on a LG refrigerator? Error code FS on LG refrigerator models indicates Freezer temperature sensor short circuit or open circuit — freezer thermistor malfunction. This error is detected by the appliance’s internal diagnostic system and displayed to alert the user that attention is needed. Refer to the troubleshooting steps above for guidance on resolving this issue.

Section titled “How do I know if my LG refrigerator is maintaining the correct temperature when FS is active? Place a separate digital thermometer in the freezer compartment to monitor actual temperature independently of the control panel display. A properly functioning freezer should maintain 0°F (-18°C) or below. If the thermometer reading deviates significantly from 0°F, the compressor cycle is not compensating correctly for the missing sensor signal and food safety is at risk. Reference: LG official support documentation (lg.com/us/support) and authorized service guides ### Is it safe to keep using my LG LRSXS26366S with error FS? If error FS does not indicate an immediate safety hazard such as a gas leak, electrical short, or water flooding, you can continue limited use while monitoring the appliance. However, running the refrigerator with an active error code increases the risk of further damage. Address the underlying issue as soon as possible. For high-severity errors, disconnect the appliance and contact a qualified technician. ### How much does it cost to fix error FS on a LG LRSXS26366S? Repair costs for error FS on the LG LRSXS26366S refrigerator depend on the root cause. DIY fixes such as cleaning filters, resetting the unit, or reconnecting loose wires cost nothing beyond basic tools. If a component replacement is needed, parts and labor from a certified technician are the main expenses. Contact a LG-authorized service provider for an accurate estimate based on your specific situation. ### What does error code FS mean on a LG refrigerator? Error code FS on LG refrigerator models indicates Freezer temperature sensor short circuit or open circuit — freezer thermistor malfunction. This error is detected by the appliance’s internal diagnostic system and displayed to alert the user that attention is needed. Refer to the troubleshooting steps above for guidance on resolving this issue.”