Dishwasher shows E19; often related to the heat exchanger or auxiliary valve control.

Safety: Disconnect power and water before accessing side panels.

E19 is associated with a small electrically controlled valve, often in the heat exchanger or softener system.

• Access side components: Remove the left side panel to locate the regeneration valve and any small solenoid valves attached to the heat exchanger or softener.
• Check connectors: Ensure all valve connectors are firmly seated and free of corrosion.
• Measure coil resistance: Use a multimeter to check each valve coil. An open circuit indicates a failed valve.
• Inspect for leaks or blockages: Ensure the valve is not clogged with limescale or debris. Clean or replace as needed.
• Replace faulty valve: Install a new Neff regeneration valve / auxiliary valve if the original is defective.

If all valves test OK, the control module may have a driver fault and require replacement by a professional.