Digital Maxmatic disposal shows E09 and stops whenever the dishwasher runs, or when water backs up from the dishwasher inlet.

Safety first: Turn off power to the disposal and turn off the dishwasher before working on the drain connections.

• Inspect dishwasher inlet: Remove the dishwasher drain hose from the Maxmatic inlet port. Check for food debris or plastic plugs blocking the port. On new installations, ensure the knockout plug has been fully removed.
• Clean the inlet passage: Use a small brush or screwdriver to clear any buildup inside the inlet fitting on the disposal.
• Check the hose: Inspect the dishwasher drain hose for kinks, sags, or clogs. Flush it with water if necessary.
• Reset the control: After clearing the blockage, reset the disposal by turning off the breaker for 2–3 minutes, then restore power and test with a short dishwasher drain cycle.

If E09 continues and water backs up into the dishwasher, the internal inlet passage or backflow sensor may be damaged, requiring replacement of the disposal or control module.