LG Oven Error Code F3: Open Temperature Sensor

The Logic Verdict

LG’s own support clip explains that F3 is the range’s way of saying “open oven sensor.” Their technician presses Clear/Off to silence the beeper, hard-resets the range at the breaker for a couple of minutes, and confirms the code only returns when the sensor circuit stays open. That tracks with field repairs: if the harness or probe measures infinite resistance, the control never sees cavity temperature and trips F3 until the probe is replaced.

What It Means

F3 = the oven temperature sensor circuit is open. The board expects roughly 1080 Ω at room temperature from the stainless probe in the rear wall. If the harness is unplugged, the sensor failed, or a splice burned open, the control reads “OL,” halts the bake cycle, and beeps F3.

Common Causes

• Loose sensor connector. The two-pin plug behind the rear panel can wiggle loose when the range is moved or steam condenses on it.
• Failed 6322B62214A probe. Heat cycling eventually breaks the internal thermistor, leaving the circuit open.
• Damaged harness. Rodents or pulled wiring can break the leads between the probe and control board.
• Latched control board. Power surges may freeze the relay logic; a full reset often clears a ghost code before you start tearing the unit apart.

Step-by-Step Fix

1. Reset the range. Press Clear/Off to stop the alarm, then cut power at the breaker for 1–2 minutes exactly as the LG video shows. Restore power and run a quick Bake test. If the display stays clear, the control just needed a reboot.
2. Check continuity at the sensor. Kill power again, remove the oven racks, and back out the single Phillips screw holding the rear sensor bulb. Gently pull the probe forward until the plug appears. Disconnect it and measure the sensor pins—anything far from ~1080 Ω at 70°F confirms the probe is open and must be replaced.
3. Inspect the harness if readings look good. If the probe ohms correctly, flip the breaker back off, remove the rear cover, and trace the sensor harness to the main board. Look for burnt spots or broken insulation and repair/replace the harness as needed.
4. Install a new sensor. Clip the replacement 6322B62214A probe into the harness connector, tuck the wires back through the liner, and secure the probe with its screw. Make sure the gasket seats flush so no heat leaks around it.
5. Power up and verify. Restore power, set the oven to 350°F, and watch the display. The temperature should climb normally with no beeping; once the board sees a valid resistance change, F3 clears automatically.

Parts & Tools

• LG 6322B62214A temperature sensor (direct replacement for open F3 probes)
• Klein MM400 multimeter (checks the probe’s 1080 Ω spec safely)

Resources