Prusa 3D Printer Error Code 10: How to Fix It

Q: What causes Prusa MMU2 Error Code 10?

Error Code 10 is triggered when the MMU2 unit detects that filament cannot be loaded, moved, or unloaded correctly — usually because it is physically stuck somewhere in the filament path. Common causes include broken filament fragments in the selector, a kinked or heat-damaged PTFE tube, a clogged nozzle, incorrect MMU2 bowden length calibration, or filament that has become brittle and snapped mid-feed.

Q: How do I prevent MMU2 filament jams from happening again?

To reduce the chance of future jams: always use good-quality 1.75mm filament with consistent diameter, store filament in sealed dry boxes to prevent moisture absorption and brittleness, regularly inspect PTFE tubes for internal scoring or kinks, keep the nozzle clean with periodic cold pulls, and ensure your MMU2 bowden calibration length is correctly set for your specific build. Also check that the filament spool unwinds freely without resistance.

Q: Can I still print with the MMU2 disabled after Error Code 10?

Yes. If you need to finish a print urgently while troubleshooting the MMU2, you can disable the MMU2 in the printer's Settings menu and print in single-material mode directly from the extruder. This bypasses the MMU2 unit entirely and lets you continue using the printer while you resolve the jam at a later time.

Q: My MMU2 keeps jamming on the same filament slot — why?

If one specific filament channel consistently causes Error Code 10, that channel's PTFE tube, drive gear, or selector alignment is likely the problem. Inspect the PTFE tube for that slot closely for kinks, flattening near the hotend, or internal scratches. Also check that the filament spool on that slot feeds freely. If the issue persists, try swapping which spool is loaded into that slot to rule out filament quality as the cause.

Q: Do I need to replace the PTFE tube after a bad jam?

Not always, but sometimes yes. After a severe jam — especially one involving a heat creep event where the filament melted higher up in the tube — the inner surface of the PTFE tube can become rough, scratched, or deformed. Inspect the tube carefully by holding it up to light. If you see discoloration, internal scoring, or any section that is no longer round and smooth, replace the PTFE tube. Replacement PTFE tubing is inexpensive and sold in standard 2mm inner diameter / 4mm outer diameter sizes compatible with the MMU2.

Abstract

Prusa Error Code 10 appears on the MMU2 multi-material upgrade unit when filament becomes stuck or jammed somewhere along the filament path — either in the selector, the PTFE tubes, or at the extruder. This is a medium-severity error that stops your print job to prevent further damage to the printer. The good news is that most filament jams on the MMU2 can be resolved at home with basic tools and a few careful steps.