Oven will not heat properly and displays F3 shortly after starting a cycle

Safety first: Disconnect power at the breaker before removing any panels or touching wiring.

• Access sensor: Inside the oven cavity, locate the temperature sensor probe on the rear wall. Remove the mounting screws and gently pull the sensor forward to expose the connector.
• Test sensor continuity: Disconnect the sensor and measure resistance with a multimeter. An open reading (OL) indicates a failed sensor. Replace with the correct La Cornue sensor for your model.
• Inspect harness: If the sensor tests good, trace the harness from the sensor to the EOC. Look for cuts, burns, or pinched sections, especially where it passes through the rear insulation and chassis.
• Check board connection: Remove the control panel to access the EOC. Verify the sensor connector is fully seated and that pins are not bent or corroded. Clean lightly with contact cleaner if needed.
• Replace faulty component: Replace the sensor or harness as required. If both are good and F3 persists, the sensor input circuit on the EOC is likely defective and the board should be replaced.