F1-4 error code, oven will not heat or shuts down shortly after starting

Safety First: Disconnect power at the breaker before testing or removing parts.

• Access the sensor: Remove the oven racks. Locate the sensor on the rear wall and remove its mounting screws. Gently pull it forward to access the connector.
• Test sensor resistance: With the sensor unplugged, measure resistance at room temperature. A reading significantly below ~1000 Ω or near 0 Ω indicates a shorted sensor.
• Inspect wiring: Follow the sensor wires as far as you can. Look for melted insulation, especially near the back of the oven where wires pass close to the liner.
• Check at control board: Remove the rear panel behind the control. Unplug the sensor connector at the EOC and measure resistance there to rule out harness issues.
• Replace faulty parts: Replace the oven temperature sensor if readings are low/shorted. If wiring and sensor are good but F1-4 remains, replace the EOC.