LG Range Error Code F5

The F5 code on an LG range means the warming drawer thermistor has shorted for more than one minute while the warming drawer was operating. The thermistor is the temperature sensor that the control board uses to regulate warming drawer heat. When the sensor signal falls into a shorted range, the control board flags the fault to prevent unsafe operation. The root cause can be the sensor itself, the wiring harness, or the control board.

You should avoid using the warming drawer while the F5 error is active, as the control board cannot accurately monitor temperature without a functioning thermistor. The rest of the range may still operate normally, but continued use of the warming drawer under this fault condition could result in unregulated heating. It is best to resolve the fault before relying on the warming drawer again.

Unplugging the range or disconnecting power may temporarily clear the F5 code, but the error will return as soon as the warming drawer operates again if the underlying fault has not been corrected. A reset does not fix a shorted thermistor or damaged wiring. Permanent resolution requires identifying and replacing or repairing the faulty component.

A knowledgeable DIYer can tackle the initial diagnostics by unplugging the range, locating the warming drawer thermistor, disconnecting it from the harness, and measuring its resistance with a multimeter. A reading near zero ohms or far below approximately 50 kilohms at room temperature confirms a shorted sensor that needs replacement. Harness repairs and control board replacement are also possible for those comfortable with appliance wiring, but working inside the range does require safe power disconnection practices.

If only the thermistor needs replacement, parts typically cost in the range of $15 to $50 depending on the specific model. Professional labor to diagnose and replace the sensor generally adds $75 to $150 or more. If the control board is the cause, board replacement parts can range from $100 to $300 or higher, and total repair costs including labor may reach $200 to $450.