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Appliance Error Codes

What Does IS Error Mean on LG LRFXS2503S?

Error IS on LG LRFXS2503S: Ice maker sensor short circuit or open circuit — ice room thermistor malfunction. Follow the troubleshooting steps below to diagnose and fix this refrigerator issue. The IS error code on your LG LRFXS2503S refrigerator indicates the ice maker sensor (ice room thermistor) has a short or open circuit fault. The ice maker sensor monitors the temperature of the ice compartment to determine when conditions are right for ice making and to detect ice jams. IS typically requires replacing the sensor, which is a straightforward repair. ## What Does IS Mean? The IS error on the LRFXS2503S indicates the control board detected an abnormal resistance reading from the ice room sensor — either too high (open circuit) or too low (short circuit). This sensor is specifically located in the ice maker compartment, separate from the main freezer temperature sensor. On LG French Door models like the LRFXS2503S, the ice maker is mounted in the upper left of the freezer door or in the door compartment. On the LRMVS3006S, the Craft Ice maker is located in a separate compartment. The IS code applies when this ice compartment sensor malfunctions. While IS does not directly affect the main cooling function of the refrigerator, the ice maker will be disabled and may generate error alerts until the sensor is repaired. ## Possible Causes 1. Failed ice room thermistor with an open circuit from thermal cycling 2. Failed ice room thermistor with a short circuit from moisture 3. Loose or corroded connector between the sensor and the control board 4. Damaged sensor wiring routed through the door hinge area that becomes pinched over time 5. Failed main control board sensor circuit ## Troubleshooting Steps | Step | Action | Expected Result | |------|--------|-----------------| | 1 | Remove all ice from the ice bin and disconnect power to the LRFXS2503S | Refrigerator is unplugged | | 2 | Locate the ice room sensor — on most LG French Door models it is a small probe mounted in the ice maker housing; consult the model-specific service diagram for its exact location | Ice room sensor is located | | 3 | Disconnect the sensor connector and measure resistance with a multimeter at room temperature; a normal reading is approximately 5,000 to 12,000 ohms at 77°F (25°C); OL confirms an open circuit; near zero confirms a short | Sensor resistance confirms normal or failed | | 4 | If sensor is failed, replace it with the correct part number for your LRFXS2503S; ensure the replacement is seated in the same position as the original | New sensor is installed correctly | | 5 | Reconnect all wiring and restore power; allow the ice maker to complete one full ice-making cycle to confirm IS has cleared | IS does not return after one complete ice cycle | The ice maker sensor operates at low voltage (typically 5V DC) and does not present a shock hazard, but always disconnect main power before opening the ice maker housing. ## When to Call a Technician Contact LG authorized service if: - The sensor tests good but IS persists — the control board sensor input circuit has failed

  • The sensor wiring harness passes through the door hinge and requires specialized routing to replace Professional repair costs for IS issues typically range from $60 to $200 depending on the specific component and your service region. ## Frequently Asked Questions ### Will the IS code stop my LG refrigerator from cooling? No. The IS error is specific to the ice maker sensor and does not affect the main refrigerator or freezer cooling functions. The compressor, fans, and defrost systems continue to operate normally. Only the ice maker will be disabled or produce reduced ice while IS is active.

Can the IS code appear on an LG refrigerator without an ice maker? The IS code only applies to models with an ice maker. If your LRFXS2503S does not have an ice maker installed, IS should not appear. Some LG models can be installed with or without an optional ice maker, and the IS code would only display if an ice maker kit is installed.

Section titled “Can the IS code appear on an LG refrigerator without an ice maker? The IS code only applies to models with an ice maker. If your LRFXS2503S does not have an ice maker installed, IS should not appear. Some LG models can be installed with or without an optional ice maker, and the IS code would only display if an ice maker kit is installed.”

My LG LRMVS3006S shows IS — is this the regular ice maker or the Craft Ice maker? The LRMVS3006S has both a standard ice maker and a separate Craft Ice maker. IS specifically refers to the ice room sensor for the standard ice maker compartment. If the Craft Ice maker has an issue, it typically displays a different diagnostic code. Check which ice type has stopped being produced to help narrow down which sensor is affected.

Section titled “My LG LRMVS3006S shows IS — is this the regular ice maker or the Craft Ice maker? The LRMVS3006S has both a standard ice maker and a separate Craft Ice maker. IS specifically refers to the ice room sensor for the standard ice maker compartment. If the Craft Ice maker has an issue, it typically displays a different diagnostic code. Check which ice type has stopped being produced to help narrow down which sensor is affected.”

How long does it take the ice maker to restart after replacing the IS sensor? After installing a new sensor and restoring power, allow 24 to 48 hours for the ice maker to resume normal production. The ice maker thermostat needs to verify the compartment is at the correct temperature before initiating a freeze cycle. The first ice batch may be smaller than normal as the system re-establishes its baseline. Reference: LG official support documentation (lg.com/us/support) and authorized service guides ### Is it safe to keep using my LG LRFXS2503S with error IS? If error IS 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 IS on a LG LRFXS2503S? Repair costs for error IS on the LG LRFXS2503S 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 IS mean on a LG refrigerator? Error code IS on LG refrigerator models indicates Ice maker sensor short circuit or open circuit — ice room 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 long does it take the ice maker to restart after replacing the IS sensor? After installing a new sensor and restoring power, allow 24 to 48 hours for the ice maker to resume normal production. The ice maker thermostat needs to verify the compartment is at the correct temperature before initiating a freeze cycle. The first ice batch may be smaller than normal as the system re-establishes its baseline. Reference: LG official support documentation (lg.com/us/support) and authorized service guides ### Is it safe to keep using my LG LRFXS2503S with error IS? If error IS 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 IS on a LG LRFXS2503S? Repair costs for error IS on the LG LRFXS2503S 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 IS mean on a LG refrigerator? Error code IS on LG refrigerator models indicates Ice maker sensor short circuit or open circuit — ice room 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.”