Display shows E16; machine may not detect the bean hopper or may refuse to grind.

Safety first: Turn off and unplug the machine before adjusting the bean hopper.

Step-by-step checks:

• Remove and reseat hopper: Lift off the bean hopper (if removable), check for obstructions, then reinstall it fully until it locks.
• Check hopper lid: Some models require the lid to be closed to operate. Ensure it is properly closed.
• Inspect for damage: Look for broken plastic tabs or magnets on the hopper that interact with internal sensors.

When to call a technician: If E16 remains with the hopper correctly installed, the presence switch or sensor may be defective and should be replaced by a professional.