Show Notes
Every Prusa error screen on the MK4, MINI, XL, CORE One and MK3.5 carries a five-digit XXYZZ code that tells you the device and problem category, and for MMU2S and MMU3 owners the 04xxx family shows whether a stopped multicolor print needs a cleaned filament path, a checked cable
In this episode you'll learn:
Newer Prusa firmware on the MK4, MINI, XL, CORE One and MK3.5 shows the error name, a short description, a five-digit code and a QR code that opens a dedicated Prusa Knowledge Base article for that exact error.
The code follows the XXYZZ pattern; Prusa's own documentation uses 12201 as the example, a MINI bed heating failure shown on screen as 'Heating failed bed'.
The first two digits identify the device, and 04 is reserved for the MMU unit (both the older MMU2S and the current MMU3); the third digit is the category: 1 mechanical, 3 electrical (typically motor drivers), 4 communication, 5 system states including incompatible firmware.
04402 is the general MMU communication error and 04504 is a firmware update request; mechanical errors in the 041xx range are the most common in practice, usually triggered when the FINDA sensor or the extruder filament sensor does not see filament where expected.
The most common cause of MMU jams is a badly formed filament tip after it is pulled out of the hotend, and Prusa lists which printers show QR error codes in its public Prusa-Error-Codes repository on GitHub.
Read the full guides on our site: Prusa Error Codes Explained: MK4, MINI, XL and Core One · MMU Error Codes 04xxx: Why Multi-Material Jams and How to Fix It
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We 3D-print custom props and game pieces for Z-AGENCY and TerraHunt.
This show is our AI bonus channel: episodes are automatically generated audio editions of the articles we publish at printara3d.com, so you can follow our topics on the go.
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