LG Oven F3 Error: Control circuit fault
LG oven error — here’s what you need to know. The F3 error code on your LG oven indicates oven control circuit fault. This is a High severity issue. What Does F3 Mean on an LG Oven? The F3 error code signals a fault in the oven’s control circuit — typically reported when the control […]
~60%
DIY Fixable
From 5
Typical Repair Cost
30–60 min
Pro Repair Time
Quick Assessment
Answer to continue safely
Is it safe to keep using?
No. Do not use the oven. F3 means the board cannot trust the temperature data it is receiving, making safe temperature regulation impossible.
Can I reset the code?
Yes. Power cycling temporarily clears F3, but the code will return as soon as the board reads the faulty sensor signal again. The root cause must be repaired.
When to stop immediately?
Stop if you notice: Stop if the sensor resistance reads near 0 ohms — this indicates a dead short requiring professional assessment., Stop if you find damaged wiring inside the oven cavity conduit..
Symptoms You May Notice
Oven shuts down heating immediately after being started
The control board detects an abnormally low sensor resistance suggesting an extreme temperature and cuts heating within seconds of activation as a safety measure.
F3 code appears on the display
The oven shows F3 with audible beeping; clearing the code and attempting to use the oven causes it to return almost instantly.
No oven modes are available
All heating functions — bake, broil, convection — are locked out by the control board until the fault condition is resolved.
Inconsistent temperature performance
The oven runs too hot, too cold, or cycles erratically because the control board receives inaccurate temperature readings from the faulty sensor.
Possible Causes
Shorted oven temperature sensor
The sensor probe has failed internally or been damaged by moisture, producing resistance far below the normal 1,080-ohm range and signaling a false over-temperature condition.
DIY PossiblePinched sensor wiring shorting to chassis
A wire in the sensor harness has been pinched against the oven cabinet wall, creating a direct short that reads as a near-zero resistance on the sensor input.
DIY PossibleFaulty oven control board
The control board has failed and is generating a false F3 fault even when all connected components — the sensor, wiring, and heating elements — test correctly.
Requires ProfessionalSafe Checks You Can Do
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1
Power cycle the oven
Switch off the oven's circuit breaker for 60 seconds and restore power. Note whether F3 reappears immediately at startup or only after attempting to use the oven.
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2
Test sensor resistance
With the oven circuit off, disconnect the sensor harness and measure resistance across the sensor terminals. A good sensor reads 1,080–1,090 ohms at room temperature. A reading below 500 ohms indicates a shorted sensor.
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3
Inspect harness for pinch points
Trace the sensor wiring from the probe through the oven rear wall and check for any point where the insulation appears compressed, cut, or in contact with a metal edge.
When to Call a Professional
Contact a qualified technician if:
- F3 persists after replacing the oven temperature sensor.
- Wiring damage is found in the internal oven conduit.
- Control board requires replacement.
Need Professional Help?
Find qualified technicians in your area for proper diagnostics and repair.
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