Washer-dryer will not start a program; display shows E01 immediately after pressing Start.

Safety first: Unplug the appliance from the mains before removing any panels. Do not bypass the door lock for testing while the machine is connected to power.

• Check door closure: Open and firmly close the door. Ensure no laundry is trapped between the door seal and the door glass. Try starting the program again.
• Inspect door hook: Examine the plastic door hook/striker on the door of your Liebherr washer-dryer combo. If it is cracked, loose, or worn, it may not engage the door interlock. Replace the door hook if damaged.
• Test door lock: Remove the front retaining band of the door gasket and gently pull back the seal to access the door lock assembly. Check that the wiring connector is fully seated and not burnt. With power disconnected, use a multimeter to test continuity of the door interlock terminals according to the wiring diagram. Replace the door lock assembly if it does not change state when the door is closed.
• Check harness and PCB: Inspect the wiring harness from the door lock to the main control board (Liebherr electronic module). Look for broken wires, corrosion, or loose connectors. Reseat connectors. If the lock and wiring are good, the main PCB may be defective and should be diagnosed and replaced by a qualified technician.