Oven will not heat properly, F3 error appears during preheat or mid-cycle

Safety first: Disconnect power at the breaker before accessing internal wiring.

• Access sensor: Locate the temperature sensor probe inside the oven cavity (rear wall, usually upper left or center). Remove the two screws and gently pull the sensor forward.
• Test resistance: Disconnect the sensor connector and measure resistance with a multimeter. At room temperature, expect ~1080 Ω at 70°F. If the reading is infinite (open) or extremely high, the sensor is bad.
• Check harness: If the sensor tests good, inspect the harness from the sensor to the main control board on your Café range. Look for broken insulation, burned spots, or loose pins at the board connector.
• Reseat connectors: Reseat the sensor connector at both ends. Restore power and test. If F3 persists with a good sensor and wiring, the control board input circuit is likely faulty.
• Replace part: Replace the oven temperature sensor (RTD) first. If the error remains, replace the electronic range control (ERC).