LG range displays F3 and oven will not heat or stops mid-cycle.

Safety first: Disconnect power at the breaker before testing or replacing parts.

• Access sensor: Locate the oven temperature sensor inside the oven cavity (rear wall). Remove the mounting screws and gently pull the sensor forward to access the connector.
• Test sensor: Disconnect the sensor and measure resistance with a multimeter. At room temperature, expect ~1080 Ω. If reading is open (OL) or far from spec (e.g., <800 Ω or >1400 Ω), replace the sensor.
• Check harness: If the sensor tests good, inspect the harness from the sensor to the control board for cuts, burns, or loose connections. Reseat the connector at the control board.
• Replace sensor: If faulty, install a new LG-compatible oven temperature sensor. Route the wires away from hot surfaces and sharp edges, then secure the sensor back to the rear wall.
• Control board: If F3 persists with a known-good sensor and wiring, the main control board sensor circuit may be defective and require replacement.