Error Code Er IS
The Er IS code means the ice maker temperature sensor (thermistor) is reading outside its expected range. This sensor tells the main board when the ice maker mold is cold enough to begin a harvest cycle and when to fill with water. A bad sensor stops ice production because the board either never triggers a harvest or never opens the water valve to fill the mold.
Common Causes
Failed ice maker thermistor: The thermistor element opens or shorts internally. The board reads an impossible temperature and locks out ice production.
Corroded sensor connector: Moisture in the ice maker compartment corrodes the connector pins. Intermittent contact produces erratic readings and triggers Er IS.
Damaged sensor wiring: The thin wires from the thermistor run along the ice maker assembly and are vulnerable to ice buildup and mechanical stress. A broken wire creates an open circuit.
Ice maker assembly failure: On some LG models, the thermistor is built into the ice maker assembly and is not sold separately. A failure means replacing the entire ice maker module.
DIY Troubleshooting
Reset the refrigerator: Unplug the unit for 5 minutes. Plug it back in. Check if Er IS clears. If it does, monitor ice production for 48 hours. An intermittent sensor often fails again within that window.
Access the ice maker sensor: Open the freezer. Remove the ice bucket. Remove the ice maker cover panel (Phillips screws or clips). The thermistor is a small probe clipped to the ice maker mold or tray. On some models, it is integrated into the ice maker module.
Inspect the connector and wiring: Check the sensor connector for corrosion (green or white deposits). Clean corroded pins with electrical contact cleaner and a small brush. Trace the wires from the sensor to the harness, looking for breaks or damage. Repair any broken wires.
Test the thermistor: Disconnect the thermistor. Set a multimeter to the 20K-ohm range. At freezer temperature (approximately 0 degrees F), expect a reading of 14,000-18,000 ohms depending on your model. OL or 0 ohms means the sensor is bad. Consult your tech sheet for the exact expected resistance values.
Replace the sensor or ice maker assembly: If the thermistor is a standalone part, unclip the old one and clip the new sensor into the same position on the mold. If the sensor is integrated into the ice maker assembly, replace the entire ice maker module. Reconnect the harness and restore power.
Professional Repair
If the thermistor is integrated into the ice maker assembly, replacement requires removing the entire module and its water line connections. A technician ensures proper installation and tests the complete ice production cycle. TruePro's $59 diagnostic fee is credited toward the repair. We warranty all repairs for 90 days on parts and labor. CA License #51112. Same-day service is often available across LA County, Orange County, and Ventura County. Call 877-378-3111. First-time customers get 15% off labor with code NEW15.
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FAQ
What does LG error code Er IS mean?
The Er IS code means the ice maker temperature sensor (thermistor) is reading outside its expected range. This sensor tells the main board when the ice maker mold is cold enough to begin a harvest cycle and when to fill with water. A bad sensor stops ice production because the board either never triggers a harvest or never opens the water valve to fill the mold.
Can I fix error code Er IS myself?
1. Reset the refrigerator: Unplug the unit for 5 minutes. Plug it back in. Check if Er IS clears. If it does, monitor ice production for 48 hours. An intermittent sensor often fails again within that window. 2. Access the ice maker sensor: Open the freezer. Remove the ice bucket. Remove the ice maker cover panel (Phillips screws or clips). The thermistor is a small probe clipped to the ice maker mold or tray. On some models, it is integrated into the ice maker module. 3. Inspect the connector and wiring: Check the sensor connector for corrosion (green or white deposits). Clean corroded pins with electrical contact cleaner and a small brush. Trace the wires from the sensor to the harness, looking for breaks or damage. Repair any broken wires. 4. Test the thermistor: Disconnect the thermistor. Set a multimeter to the 20K-ohm range. At freezer temperature (approximately 0 degrees F), expect a reading of 14,000-18,000 ohms depending on your model. OL or 0 ohms means the sensor is bad. Consult your tech sheet for the exact expected resistance values. 5. Replace the sensor or ice maker assembly: If the thermistor is a standalone part, unclip the old one and clip the new sensor into the same position on the mold. If the sensor is integrated into the ice maker assembly, replace the entire ice maker module. Reconnect the harness and restore power.
How much does it cost to fix error Er IS?
Typical repair costs: DIY: $20 - $130 | Pro: $160 - $350. Free diagnostic with approved repair.
Estimated Cost
DIY: $20 - $130 | Pro: $160 - $350
Free diagnostic with approved repair
Need Help With This Error?
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