Water backs up into the dishwasher from the sink or garbage disposal.

Safety first: Turn off power before adjusting hoses.

• Clear sink drain: Ensure the sink and disposal drain freely. Clear any clogs.
• Install high loop: Secure the drain hose so it rises to the underside of the countertop before dropping to the sink/disposal connection.
• Check air gap: If your installation uses an air gap, remove the cap and clean out any debris.
• Verify disposal knockout: If recently installed, ensure the dishwasher knockout plug in the disposal inlet has been removed.