Hansa oven will not heat; display shows E01 shortly after turning on any heating function.

Safety first: Disconnect the oven from mains power by switching off the circuit breaker or unplugging it. Wait until all internal parts are cool before working.

• Check for obvious wiring damage: Pull the oven out enough to access the back panel. Remove the rear cover and visually inspect the cable going to the oven temperature sensor (usually a thin, shielded cable leading to a probe inside the cavity). Look for burns, cuts, or disconnected plugs.
• Inspect the temperature sensor (NTC): The sensor is typically mounted on the rear wall of the oven cavity with 1–2 screws. From the rear, locate its connector on the wiring harness and unplug it. Using a multimeter set to resistance (ohms), measure across the sensor terminals. A typical Hansa NTC will read roughly 500–1200 Ω at room temperature (exact value depends on model). If the meter shows OL (open) or extremely high resistance, the sensor is faulty and should be replaced.
• Check harness continuity: With the sensor unplugged, check continuity from the sensor connector back to the control board connector. Repair or replace any damaged wires or loose terminals.
• Reseat connectors on the control board: Remove the top cover/front control panel as needed to access the electronic control board. Carefully unplug and replug the sensor connector to ensure a solid contact.
• Replace faulty parts: If the sensor is open or out of spec, install a new OEM Hansa oven temperature sensor (NTC probe). If wiring and sensor are good but E01 persists, the control board may have a defective sensor input circuit and should be replaced or professionally repaired.

When to call a technician: If you are not comfortable using a multimeter or removing the oven from its cabinet, or if the control board appears damaged (burn marks, swollen components), contact an authorized Hansa service center.