Digital Maxmatic disposal displays E04 and shuts off shortly after starting, often under heavy load.

Safety first: Turn off the switch and allow the unit to cool for 5–10 minutes before working on it.

• Clear the chamber: Remove any large or fibrous items (corn husks, celery, bones) using tongs. Avoid grinding large quantities at once; feed small amounts with cold water running.
• Free the plate: Use the bottom hex service port with an Allen wrench to rotate the impeller plate back and forth until it moves smoothly through a full revolution.
• Reset the unit: Press the reset/overload button on the bottom of the disposal. Restore power and test with a small amount of soft food waste.
• Listen for bearing noise: If the unit sounds rough, squeals, or labors even with light load, the motor bearings may be failing and drawing excess current.

If E04 recurs with light loads and a free-spinning plate, the motor or start capacitor is likely failing and the disposal should be replaced or serviced by a technician.