Thermomix does not start a cooking program and displays C0 shortly after power‑on or when trying to heat.

Safety first: Unplug the Thermomix from the mains before any inspection. Allow the appliance to cool completely if it was recently used.

• Reset and clean contacts: Remove the mixing bowl, clean and dry the underside of the bowl and the base contacts on the machine. Ensure there is no food residue, corrosion, or moisture on the central metal contact area.
• Test with another bowl (if available): If you have access to a second compatible Thermomix bowl, insert it and check if the C0 error disappears. If it does, the original bowl’s NTC sensor or its internal wiring is likely faulty.
• Inspect base connector (advanced): With the unit unplugged, remove the bottom cover (this may void warranty). Check the small connector and wiring from the bowl temperature sensor interface to the main PCB. Reseat any loose connectors and look for broken or pinched wires.
• When to stop: If the error persists after cleaning contacts and testing another bowl, the NTC sensor or the main control board is likely defective. Do not bypass or short the sensor. Contact an authorized Thermomix service center for sensor or PCB replacement.