LG Refrigerator Error Code Freezer 2nd Digit b

This code means the main PCB has detected an abnormal reading from the freezer temperature sensor. The sensor is reporting a temperature at or above +50°C or at or below -50°C, which is outside any realistic range. This points to a wiring fault, a loose connector, or a failed sensor thermistor rather than an actual temperature problem in the freezer.

The freezer may not be maintaining proper temperature while this error is active because the control board cannot accurately read freezer conditions. Food safety is at risk if the freezer is not holding 0°F or below. It is best to address the fault promptly and transfer perishable or frozen food to another unit in the meantime if you are unsure whether the freezer is cooling correctly.

If only a connector needs to be reseated, there may be no parts cost at all. A replacement freezer thermistor sensor typically costs between $15 and $50 for the part. If the main PCB is at fault, the board can range from $100 to $300 or more depending on the model. Adding professional labor, total repair costs can range from around $75 to $400 depending on what component has failed.

A knowledgeable DIYer can start by checking the sensor wiring connector at main PCB CN30 pins #1 and #6 and measuring the voltage, which should fall between 1.0V and 4.5V. If the connector is simply loose, reseating it may clear the fault. Replacing the sensor thermistor is also a manageable repair, but working near live PCB components requires caution and basic electrical safety knowledge.

A power reset may temporarily clear the error display, but the code will return if the underlying fault in the sensor circuit has not been repaired. Resetting does not fix a cut wire, slipped connector, or failed thermistor. The CN30 voltage should be measured and the sensor circuit inspected to resolve the issue permanently.