Dishwasher overfills or shows E4; water may be visible in the base tray and the machine may run the drain pump continuously.

Safety first: Disconnect power and close the water tap. Be prepared for water spillage.

Step-by-step checks:

• Check for leaks: Pull the dishwasher out and inspect the base tray. If water is present, the anti-flood float switch will trigger E4. Sponge out all water and dry the base completely.
• Inspect hoses and clamps: Run a short fill cycle while observing the machine (with side panels removed if possible). Look for drips from the circulation pump, heater housing, inlet valve, or internal hoses.
• Check pressure switch and air trap: Vestel dishwashers often use a pressure switch connected via a small hose to the sump or side chamber. Remove the hose and blow through it to clear grease or limescale. Ensure the air trap is not blocked.
• Test inlet valve closure: With power off, inspect the inlet valve for debris preventing closure. If the machine continues to fill even when power is off, the valve is mechanically stuck and must be replaced.
• Float switch: Verify that the float in the base tray moves freely and that its microswitch clicks when actuated. Replace if stuck or defective.

After repairs, reset the error by unplugging for several minutes and run a test cycle while monitoring for leaks.