LG Refrigerator Error Code 10

Error code 10 on an LG refrigerator indicates an abnormality in the defrost sensor system for the CF (convertible freezer) compartment. This sensor monitors temperatures during defrost cycles, and the unit flags this code when the sensor reports a temperature that falls outside the expected range: not lower than -58°F and not higher than 122°F. When the sensor reading lands outside these bounds, the control board interprets it as a system fault rather than a valid temperature reading.

The fault can originate from several physical conditions along the sensor circuit. A broken or cut wire will interrupt the signal entirely, causing the control board to receive no data or an out-of-range reading. A short circuit in the wiring harness can pull the signal voltage to an abnormal level. Poor contact at a connector, corroded terminals, or a loose plug at either the sensor or the board can produce intermittent or incorrect resistance readings. A missing or improperly seated sensor housing can also cause the sensor element to read ambient temperatures instead of the compartment temperature it is designed to monitor.

The defrost sensor itself can fail internally, producing a resistance value that corresponds to a temperature outside the valid detection range. Defrost sensors typically change resistance with temperature, and a failed sensor may read open or shorted, both of which push the reported temperature beyond the -58°F to 122°F window the control board uses to validate the signal. Diagnosis should begin with a visual inspection of the wiring and connectors before testing sensor resistance with a multimeter.