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                  1. Support
                  2. QR Error codes
                  3. Unload manually #04506 (MMU)
                   

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                  Unload manually

                  #04506 (MMU)

                  Relevant for

                  MMU2S
                  MMU3
                  24 comments
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                  What happened?

                  Implausible SuperFINDA sensor reading. This error occurs when the SuperFINDA sensor detects filament inside the Selector, but the MMU has no record of any filament being loaded. As a result, it cannot determine which filament position is loaded and cannot automatically unload.

                  This often happens due to a malfunctioning or improperly calibrated SuperFINDA sensor.

                  Another potential cause could be the filament being inserted into the selector manually, bypassing the menu/buttons, or restarting the printer during a load/unload operation before it is completed.

                  How to fix it?

                  • Verify there is no filament in the Selector, and the SuperFINDA sensor isn’t detecting a filament.
                  • If the filament is loaded, unload it manually or clear any obstructions triggering the SuperFINDA sensor.
                  • On the MK3/S and MK3.5/S Re-calibrate the SuperFINDA sensor.
                  • See the FINDA troubleshooting article.
                  • Use only the printer menu to load or unload filament during regular use.
                  Was this article helpful?
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                  Topics

                  • Troubleshooting
                    • QR Error codes
                      • FINDA didn't trigger #04101 (MMU)
                      • FINDA: Filament Stuck #04102 (MMU)
                      • Filament sensor didn't trigger #04103 (MMU)
                      • Filament sensor: Fil. stuck #04104 (MMU)
                      • Pulley cannot move #04105 (MMU)
                      • Idler cannot home #04125 (MMU)
                      • Selector cannot home #04115 (MMU)
                      • Selector cannot move #04116 (MMU)
                      • Filament sensor too early #04106 (MMU)
                      • Inspect FINDA #04107 (MMU)
                      • MMU Overcurrent #31310 (CORE One) #35310 (CORE One L) #26310 (MK4S) #13310 (MK4) #27310 (MK3.9S) #21310 (MK3.9) #28310 (MK3.5S) #23310 (MK3.5)
                      • Load to extruder failed #04108 (MMU)
                      • Unload manually #04506 (MMU)
                      • Filament ejected #04507 (MMU)
                      • MMU Selftest failed #04305 (MMU)
                      • MMU not responding #04401 (MMU)
                      • Communication error #04402 (MMU)
                      • Firmware update needed #04504 (MMU)
                      • Firmware runtime error #04505 (MMU)
                      • TMC driver error #04301 (MMU)
                      • Invalid tool #04502 (MMU)
                      • Filament already loaded #04501 (MMU)
                      • Queue full #04503 (MMU)
                      • Unknown error #04900 (MMU)
                      • Warning: TMC too hot #04201 (MMU)
                      • Warning: TMC too hot #04211 (MMU)
                      • Warning: TMC too hot #04221 (MMU)
                      • TMC overheat error #04202 (MMU)
                      • TMC overheat error #04212 (MMU)
                      • TMC overheat error #04222 (MMU)
                      • TMC Driver reset #04302 (MMU)
                      • TMC Driver reset #04312 (MMU)
                      • TMC Driver reset #04322 (MMU)
                      • TMC Undervoltage error #04303 (MMU)
                      • TMC Undervoltage error #04313 (MMU)
                      • TMC Undervoltage error #04323 (MMU)
                      • MMU MCU Error #04306 (MMU)
                      • TMC driver error #04311 (MMU)
                      • TMC driver error #04321 (MMU)
                      • MMU Selftest failed #04315 (MMU)
                      • MMU Selftest failed #04325 (MMU)
                      • Filament change #04508 (MMU)
                      • MMU MCU Underpower #04307 (MMU)
                      • TMC driver shorted #04304 (MMU)
                      • TMC driver shorted #04314 (MMU)
                      • TMC driver shorted #04324 (MMU)
                      • Print preview MMU filament inserted #31806 (CORE One) #26806 (MK4S) #13806 (MK4) #27806 (MK3.9S) #21806 (MK3.9) #28806 (MK3.5S) #23806 (MK3.5)
                      • Print preview tools mapping #31814 (CORE One) #36814 (CORE One INDX) #17814 (XL) #26814 (MK4S) #13814 (MK4) #27814 (MK3.9S) #21814 (MK3.9) #28814 (MK3.5S) #23814 (MK3.5)
                      • MMU load unload error #31815 (CORE One) #26815 (MK4S) #13815 (MK4) #27815 (MK3.9S) #21815 (MK3.9) #28815 (MK3.5S) #23815 (MK3.5)
                      • Maintenance warning #31117 (CORE One) #26117 (MK4S) #13117 (MK4) #27117 (MK3.9S) #21117 (MK3.9) #28117 (MK3.5S) #23117 (MK3.5)
                      • Maintenance failure warning #28116 (MK3.5S) #23116 (MK3.5)
                      • Maintenance failure warning #31116 (CORE One) #26116 (MK4S) #13116 (MK4) #27116 (MK3.9S) #21116 (MK3.9)
                    • Diagnostics
                    • Print Quality Troubleshooting
                    • Printer troubleshooting
                    • Print Error Messages

                  10 comments

                  Log in  to post a comment
                  FrogChamp
                  •
                  ive has this error all day i tried everything, printer is completely locked up, can't update mmu, i tried moving the FINDA i tried outirght uninstalling it i tried reseting the mmu but it just won't stop
                  Reply
                  greed fox
                  •
                  core one + / MMU3 lite
                  after some time working my finda had moved down slightly, I nudged it up slightly, reset the printer and manually calibrated the finda by looking at the light on the side of it.

                  once finda was moved up and calibrated it works fine.
                  Reply
                  surdumil
                  •
                  I received this error and basically cut up all of the filament in the feed path and did a bunch of other things. In the end, though, the solution was simple.

                  After getting all the filament out of the path, I had not noticed that there was still a short length of filament in the MMU3's output feed tube that was holding the FINDA in ON state. I removed that filament and I was able to get past that error screen. It was might frustrating until I found and removed that piece of filament.
                  Reply
                  electrodraco
                  •
                  Received this warning right after starting up my core one. The only option available now is to "Retry". Printer is completely locked and it is impossible to start any re-calibration procedure.

                  Of course there is no filament in the FINDA, the ball moves freely, and frankly, not even sure how there could be any reading since the MMU has not even initialized.

                  Yet again the printer is telling me bullshit while the Prusa manual can't offer a single solution that remotely works. It is as if none of these processes were tested before unleashing them onto the customer.
                  Reply
                  alkali_feldspar
                  •
                  Had the same issue during initial setup. For me the probe was too close to the ball. As soon as I moved it back a bit, everything worked.
                  Reply
                  JellyBagel
                  •
                  Which sensor are you referring to?
                  Reply
                  chrisw
                  •
                  Hello everyone I'm having a problem with the MMU3 on my Core One. I'm getting an error message saying I have to manually remove the filament. I did that because it was jammed, but now I can't fix the error message; it keeps popping up. Can anyone help me? Thank you.
                  Reply
                  chr1s123
                  •
                  Move the sensor up a bit . Way I calibrated it was if there was fillament in and triggered but didn’t trigger without
                  Reply