Dishwasher runs but then stops and displays C1; unit may attempt to drain continuously.

Safety first: Turn off power at the breaker and shut off the water supply before working on the dishwasher. Be prepared for some water spillage when disconnecting hoses.

• Check the sink/disposal connection: If the dishwasher drain hose connects to a garbage disposal, ensure the disposal is clear. Run the disposal with water for 30–60 seconds. If the disposal is new, verify the knockout plug was removed from the dishwasher inlet.
• Inspect the air gap (if installed): Remove the air gap cap at the sink and check for food debris or grease buildup. Clean thoroughly and flush with hot water.
• Clean the dishwasher filter and sump: Remove the lower rack. Twist and lift out the fine filter assembly at the bottom of the tub. Rinse under hot water and scrub off debris. Look into the sump area with a flashlight and remove any food, glass, or labels that may block the drain path.
• Check the drain hose: Access the drain hose under the sink and behind the dishwasher. Ensure there are no kinks or sharp bends. Detach the hose from the sink/disposal connection and blow through it or flush with water to confirm it is not clogged.
• Test operation: Restore power and run a short cycle. If C1 returns, the drain pump may be weak or obstructed internally and may need replacement.