Er rB
LG Refrigerator
Severity: CriticalWhat Does This Error Mean?
The Er rB error means the refrigerator compartment's main temperature sensor (thermistor) has failed. The fridge cannot accurately read or control its internal temperature. This is a high-priority issue — food safety is at risk if temperatures are not controlled.
Affected Models
- LRMVS3006S
- LRFXS2503S
- LFXS26973S
- LRMVS3006D
- Most LG French door and bottom-freezer refrigerators
Common Causes
- Refrigerator section thermistor has failed (open or short circuit)
- Wiring harness to the sensor is loose, chafed, or corroded
- Control board has stopped reading the sensor signal correctly
- Physical damage to the sensor from shelf removal or cleaning
- Moisture or condensation on the sensor connection causing intermittent faults
How to Fix It
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Check the refrigerator temperature with a separate thermometer placed inside.
If the temperature is above 40°F (4°C), move perishable food to a cooler immediately.
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Unplug the refrigerator for 10 minutes and restore power.
A full reset occasionally clears a temporary sensor communication error.
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Check the temperature again after 2 hours to see if the fridge is cooling normally.
If temperatures are stable after a reset, monitor closely for 24 hours.
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Check for any loose wiring visible at the back wall of the refrigerator compartment.
Sometimes a shelf removal during cleaning can snag and disconnect a sensor wire.
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If the error persists, contact a technician — the thermistor needs testing and replacement.
Do not ignore this error — inaccurate temperature control can spoil food quietly.
When to Call a Professional
A failed refrigerator thermistor is a time-sensitive repair — without accurate temperature sensing, the fridge may over-cool or under-cool. Contact an LG certified technician promptly. Expect repair costs of $90–$200 for sensor replacement and labor.
Frequently Asked Questions
How do I know if my LG fridge is still keeping safe temperatures during Er rB?
Place a separate thermometer (a few dollars at any kitchen store) inside the fridge. Safe refrigerator temperature is 35–38°F (2–3°C). If it is above 40°F (4°C), move perishables immediately and arrange an urgent repair.
Can I reset the Er rB error myself?
A power reset (unplug for 10 minutes) can clear it if the error was a one-time glitch. But if the thermistor has truly failed, the error will return within hours. Physical sensor replacement is the only permanent fix.
How much does a refrigerator thermistor cost?
The thermistor itself is cheap — typically $10–$30 for the part. Labor to access it and replace it is $75–$160. Total cost is usually $90–$200, making it one of the more affordable fridge repairs.