LG Dishwasher Error Code F-2

The F-2 error on an LG dishwasher indicates the control board has detected an abnormally low temperature reading, specifically 30 degrees below zero, from the thermistor circuit. This reading is physically impossible under normal operating conditions and tells a technician immediately that the fault is electrical rather than a genuine temperature condition. The most direct cause is an open thermistor circuit, meaning continuity is broken somewhere between the thermistor sensor and the control board, causing the board to read a nonsensical value. Because the thermistor governs the drying cycle, an open circuit in this path also renders the dryer inoperative.

For homeowners, the thermistor is a small temperature sensor inside the dishwasher that tells the control board how hot the water and air are. When this sensor or the wiring connected to it fails, the dishwasher cannot read temperature at all. Instead of seeing a real number, the board sees an open circuit and interprets it as a wildly low temperature, triggering the F-2 code. The dishwasher will not complete its drying cycle as a result.

The wiring harness connecting the thermistor to the control board, the thermistor itself, and less commonly the control board are the components to inspect. Resistance testing across the thermistor leads will quickly confirm whether the sensor has failed or whether the fault lies in the wiring.