LG error code F3: The oven temperature sensor circuit is open (broken). The oven cannot measure temperature and will not operate the heating elements.
The oven temperature sensor circuit is open (broken). The oven cannot measure temperature and will not operate the heating elements.
Turn off the circuit breaker for the oven at your electrical panel before performing any testing. Oven circuits carry 240V and are potentially lethal.
The oven temperature sensor is a thin metal probe mounted inside the oven cavity, usually at the top rear. Pull it slightly out from the bracket. Disconnect the wiring connector at the back of the range and test the probe for resistance. At room temperature (~70°F) it should read approximately 1,080–1,100 Ω. A reading of 0 Ω (shorted) or infinite Ω (open) means replace the sensor.
Tools needed: Multimeter, Screwdriver set
Trace the sensor wiring back to the electronic oven control board. Check for any burned insulation, bare wires, or corroded/loose connector pins. A corroded pin can mimic a bad sensor.
Tools needed: Screwdriver set
If the sensor tests out of spec, order the OEM temperature sensor for your exact model number. The sensor is typically held by one or two screws and is one of the simplest oven repairs. Route the new sensor's wires carefully away from any heating elements.
Tools needed: Screwdriver set
After replacing the sensor, set the oven to 350°F and place an oven thermometer inside. After 15–20 minutes, compare the actual temperature to the set temperature. Most ovens allow user calibration adjustments of ±35°F in the settings menu.
Tools needed: Oven thermometer