Dishwasher will not start a program, display shows E01 shortly after pressing Start.

Safety first: Disconnect the dishwasher from mains power and turn off the water supply before any work. Be prepared for water spillage when tilting the appliance.

Step-by-step checks:

• 1. Inspect for leaks under the machine: Pull the Constructa dishwasher slightly out of the cabinet. Check the floor and the base pan area for standing water. If you see water, the AquaStop system has likely been triggered.
• 2. Drain the base pan: Carefully tilt the dishwasher about 45° backwards (have towels ready). Allow any water in the base pan to drain out. Let it dry completely for several hours or use a fan to speed up drying.
• 3. Check the AquaStop hose: Follow the inlet hose from the tap to the dishwasher. If it is a thick, box-shaped AquaStop hose, inspect for bulges, cracks, or signs of leakage near the tap or at the machine connection. Tighten the connections gently; do not overtighten plastic fittings.
• 4. Inspect internal hoses and sump area: Remove the lower front kick plate (if accessible) and look for drips around the circulation pump, sump, and internal hoses. Any visible crack or loose clamp can cause the base to fill with water and trigger E01.
• 5. Reset and test: After drying the base and correcting any obvious leak, reconnect power and water, then run a short program while monitoring for leaks. If E01 returns quickly without visible leaks, the AquaStop valve assembly or float switch may be defective.

When to call a technician: If the base pan repeatedly fills with water or you cannot locate the leak source, a professional should pressure-test the internal hoses and replace the AquaStop assembly if needed.