Washer-dryer does not heat during wash; cycles take unusually long and E05 appears.

Safety first: Unplug the appliance and allow it to cool before working near the tub or heater terminals.

• Access heater: On many Liebherr washer-dryer combos, the wash heater is mounted at the rear of the tub. Remove the rear panel to access the heater terminals and NTC sensor.
• Test heating element: Disconnect the heater wires and measure resistance across the heater terminals with a multimeter. A typical value is 20–30 Ω (check Liebherr specs). Infinite resistance indicates a failed element that must be replaced.
• Check NTC sensor: Measure the resistance of the NTC temperature sensor at room temperature. Compare to service documentation; if reading is open, shorted, or far out of range, replace the NTC sensor.
• Inspect wiring and connectors: Look for signs of overheating, discoloration, or loose spade connectors at the heater and NTC. Repair or replace damaged wiring.
• Control board relay: If heater and NTC are good, the heater relay on the main PCB may be faulty. This repair involves live-voltage diagnostics and board-level work and should be done by a qualified technician.