Fix LG Oven Error Code Displayed

The temperature-sensor codes#

• F9 — open sensor circuit (most common). The thermistor or its wiring is open and the control can't read oven temperature, so it shuts down heating. Test the sensor — about 1,080 ohms at 70 degrees F — and if it reads open, check the wiring (a harness break where it enters the cavity is common) before replacing the sensor.
• F10 — shorted sensor or runaway temperature (critical). The oven shuts all elements off immediately. If the oven was cool when the code appeared, the sensor is shorted; if it was extremely hot, it's a genuine over-temp from a welded relay or a false low reading that over-fired the oven.

Element, latch, and control codes#

• F3 / F4 (elements). F3 is an open bake element — the most common single-component failure in ovens — and F4 is the same for the broil element. Test the element's continuity across its terminals.
• F1 (control board). The board's microcontroller hit an internal error. Power-cycle for 5 minutes; if F1 returns immediately, the board has failed — power surges are the usual culprit.
• F5 (door latch). The latch motor ran but the position switch didn't confirm in time — a stripped gear, failed switch, or wiring fault. It only affects self-clean.
• F7 (stuck key). A touchpad button reads as continuously pressed. Check for moisture; disconnect the touchpad ribbon, and if F7 clears the touchpad is the problem, while if it persists the board is.
• F11 (communication). On ThinQ models the WiFi module and board lost contact — the oven still cooks normally, only the smart features go offline. Some models also show CF for a convection-fan fault.

Clearing codes and urgency#

Press Clear/Off to reset to standby; if the code returns immediately the fault is live, and a code that only returns during use is intermittent and needs diagnosis. By urgency: F10 is immediate (unplug — the oven may not stop heating) and F1 is high (don't use until the board is replaced), while F9 and F3 or F4 are medium (reduced function), and F5 and F11 are low (self-clean or smart features only). LG's Smart Diagnosis — through the ThinQ app or by calling LG at 1-800-243-0000 and holding the phone to the panel — can sometimes pin down an intermittent fault.

Prevention and a holiday note#

A surge protector on the range circuit heads off the F1 board failures that surges cause; clean the temperature sensor annually so grease doesn't skew it, and keep the oven vent clear so blocked airflow doesn't trigger F10. Address intermittent codes early, because they usually mean a part is failing — and getting ahead of it before holiday baking beats a dead oven on the day. Book an EasyBear technician for any F1 or F10.