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Filament sensor didn't trigger #04103 (MMU)

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Last updated a year ago
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What happened?

If during the filament load to nozzle process, the filament sensor in the extruder is not triggered, the printer will show the error.

How to fix it?


  • Remake the filament sensor calibration.
  • Make sure that the PTFE tube is fully pushed into the Festo fitting, and that the fitting is fully tightened, with no gap.
  • Open the extruder idler and make sure that there is no leftover filament in the extruder blocking the new filament from loading.
  • Make sure that the PTFE tube is fully pushed into the Festo fitting.
  • If you use an alternative MMU-to-Extruder PTFE tube, make sure it is not excessively long.

    The original tube is 360mm long. The MMU will automatically adapt to tubes up to 380 mm, but will not work with tubes longer than that.




  • The filaments must have a sharp tip in order to load properly into the printer. If the tip is deformed, bent, or larger in diameter, cut it off.
  • Inspect the last 40cm (15") of each filament. Make sure there are no dents in it.
  • If the filament is still not being pulled, check the assembly.


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