Dishwasher stops during wash or rinse, shows E04 and may overfill or underfill.

Safety first: Disconnect from mains and close water supply.

• Locate pressure system: On Electrolux Professional dishwashers, the pressure switch or analog pressure sensor is usually mounted on the side or base, connected to the sump via a small hose.
• Inspect pressure hose: Remove the hose and blow through it. If blocked, clean it with hot water and a small brush or pipe cleaner.
• Clean air trap/pressure chamber: If accessible, remove the air trap from the sump and descale it using warm water and a descaling agent to remove grease and limescale.
• Check electrical connections: Ensure the connector on the pressure switch/sensor is firmly seated and free of corrosion.
• Test or replace sensor: If the error persists, replace the pressure switch or analog pressure sensor according to the model's parts list.