What happened?
This message appears during an MMU filament load or unload operation that could not be completed automatically. The printer is waiting for the user to intervene or confirm the next step. The message shown is: Waiting for user input.
This typically occurs when the filament fails to reach the expected sensor position, gets stuck during the load/unload path, or when a manual check is needed. It is most common with MMU prints or during material changes.
Error name: MMU load unload error
Error code: #31815 (CORE One) #26815 (MK4S) #13815 (MK4) #27815 (MK3.9S) #21815 (MK3.9) #28815 (MK3.5S) #23815 (MK3.5)
How to fix it?
- Follow the on-screen instructions on the printer. This may involve:
- Trimming the filament tip and reinserting it
- Manually confirming the filament has reached the extruder
- Removing the stuck filament from the selector or buffer tube
- Use the Load Filament or Unload Filament options from the LCD if needed to reset the state.
- If this happens frequently, check that:
- The MMU unit and selector are clean and aligned
- Filament is dry and has clean, sharp tips
- Tubes and paths are not restricted
Once the issue is resolved, press Continue to resume the operation. If the printer does not respond or the issue repeats, do not hesitate to contact our Support, we'll take it from here.