Machine stops mid‑cycle and displays E4; water remains in tank and will not drain.

Safety first: Disconnect power and ensure water is cool before working inside the sump or pump area.

• Manually remove standing water: Open the door and use a jug or wet‑vac to remove as much water as possible from the tank and sump.
• Clean filters and sump: Remove the internal tank filters and strainers. Clean thoroughly under running water. Check the sump area for broken glass, food debris, or limescale that could block the pump inlet.
• Inspect the drain pump: Access the drain pump assembly from the front or side. Remove the pump cover or hose to inspect the impeller. Clear any obstructions. Ensure the impeller spins freely by hand.
• Check drain hose and air break: Follow the drain hose from the pump to the waste connection. Look for kinks, crushed sections, or blockages at the sink trap. Clean the air break or non‑return valve if fitted.
• Test pump electrically: With the pump disconnected, measure coil resistance (typically 150–300 Ω for small drain pumps). An open circuit or tripped thermal protector indicates a failed pump that must be replaced.
• Verify level sensor: If the pump runs but E4 persists, check the drain level sensor / pressure switch for blockage or incorrect switching, as it may be falsely indicating a full tank.