Washer stops early in cycle, does not heat water, displays F03

Safety first: Unplug the washer and allow it to cool before accessing internal components.

• Locate NTC sensor: On Bauknecht front-loaders, the NTC (temperature sensor) is usually mounted in the heater housing at the bottom front of the tub. Access it from the rear or front lower panel depending on model.
• Check connector: Ensure the two-wire connector to the NTC is firmly seated and free of corrosion. Reseat it several times to clean contacts.
• Visual inspection: Look for signs of water ingress, limescale buildup, or burnt marks around the heater/NTC area.
• Basic resistance check (for experienced users): With the sensor disconnected and the washer unplugged, measure resistance across the NTC terminals using a multimeter. At room temperature, most Bauknecht NTCs read roughly 20 kΩ (varies by model). Infinite or near-zero resistance indicates a faulty sensor.

Next steps: If wiring is intact and readings are abnormal, replace the NTC sensor. If the NTC tests good, the fault may lie in the main control board's temperature circuit.