Oven stops heating during operation and shows E003, fan may continue running

Safety: Switch off power at the breaker before accessing the rear or internal panels.

• Locate the sensor: The temperature sensor is usually a thin metal probe protruding into the oven cavity (often at the rear upper area) with two wires leading to the control board.
• Check for physical damage: Inspect the probe for deformation, corrosion, or damage from oven cleaners.
• Test resistance: Disconnect the sensor connector and measure resistance with a multimeter. Typical Gaggenau NTC sensors measure around 1–1.1 kΩ at 20 °C (check service data for your model). A reading of 0 Ω (short) or infinite (open) indicates failure.
• Wiggle test: While measuring, gently move the cable to detect intermittent faults.
• Inspect harness and connectors: Trace the sensor wires to the control board, checking for cuts, melted insulation, or loose plugs.
• Reset and test: After reseating connectors, restore power and test a low-temperature program to see if E003 clears.

When to replace: If resistance is out of specification or intermittent, replace the temperature sensor. If the sensor and wiring are good, the main control board may be defective and should be handled by a professional.