F3
LG Oven
Severity: CriticalWhat it means
LG oven F3 error means the oven temperature sensor (RTD probe) has an open circuit — it is not sending any temperature reading to the control board.
Replace the sensor to resolve the F3 error.
Affected Models
- LG Electric Range
- LG Gas Range
- LG LRE Series
- LG LRG Series
- LG Studio Range
Common Causes
- Failed oven temperature sensor with open circuit
- Sensor wiring disconnected or burned
- Physical damage to the sensor probe from bakeware contact
- Control board fault (less common — test the sensor first)
How to Fix It
-
Perform a power reset.
Switch off the oven at the circuit breaker for 2 minutes, then restore power.
If F3 was triggered by a momentary wiring issue, a reset may clear it. -
Locate and inspect the temperature sensor.
Open the oven door and look at the upper rear wall of the oven cavity.
The sensor is a small metal probe (about 10 cm / 4 inches) projecting from the back wall.
Check for obvious physical damage or disconnected wires. -
Test the sensor with a multimeter.
At room temperature the LG oven sensor should read approximately 1,000–1,100 ohms.
An open circuit (OL / infinity) reading confirms the sensor has failed. -
Replace the temperature sensor.
LG oven sensors typically cost $15–$35.
Remove the one or two mounting screws, pull the probe out, disconnect the wire connector through the back panel, and install the new sensor.
When to Call a Professional
Oven temperature sensor replacement is a simple, low-cost repair on LG ranges.
The probe is accessed from inside the oven cavity and the connector reaches through the back wall — most homeowners can do this themselves.
Frequently Asked Questions
LG oven shows F3 intermittently — does that mean the sensor is failing gradually?
Yes — an intermittent F3 usually means the sensor has a developing fault, such as a hairline crack in the element or a loose wire connection. It will fail completely soon. Replace the sensor before it leaves you without an oven mid-cook.
Can I test my LG oven temperature accuracy if F3 is not currently showing?
Yes — use an oven thermometer placed in the centre of the oven. Preheat to 180°C (350°F) and compare the actual temperature to the set temperature. A consistent difference of more than 15°C suggests the sensor needs recalibration or replacement.