Stringing and oozing

Stringing or oozing, also known as "hairy prints", is the name given for when small strings of filament are left on a printed model. This usually happens when the filament keeps…

First layer issues

This is by far the most common 3D printing problem, and probably the first one you may encounter. The first layer is the essential one because it is the base of the printed object.…

The Benchy hull line

The 3DBenchy is a 3D model designed by CreativeTools specifically for testing and benchmarking 3D printers. And everyone wants to know, how to print a perfect Benchy. Ever since…

Clogged nozzle/hotend (MK3.5/S, MK3S+, MK2.5S)

A 3D printer's hotend can get clogged. This article explains the most common causes of this issue, which are usually the same regardless of the printer type or model. We then have…

MINTEMP error and MINTEMP BED

The MINTEMP error (written sometimes as min temp) occurs when the temperature readout from the heatbed thermistor or hotend thermistor drops below a certain amount within a certain…

Layer shifting

Layer shifting is a printing issue that causes the layers of the printed object to shift from their intended positions. It is usually associated with an abnormal movement of the…

SD cards and USB drives

As there are ways of remotely transferring files and starting prints, an SD card or USB flash drive is the most common and reliable way to get your files to your machine. Though…

Extruder noises

Filament grinding, which is accompanied by a “clicking” or "squeaking " sound coming from the extruder, usually happens when the extruder gears are unable to push the filament…

Extrusion stopped mid-print (Heat creep)

If your printer suddenly stops extruding filament, yet continues the print moves without reporting any error, you may be a victim of a heat creep. What does it look like Broadly…

Under-extrusion

You can recognize under extrusion when there is material missing in your print’s layers. Printed objects with under extruded layers can be fragile and tend to break apart. There…

P.I.N.D.A./SuperPINDA Sensor testing

P.I.N.D.A. stands for Prusa INDuction Autoleveling sensor and is a vital component facilitating the calibration of our printers. There are 3 different versions: P.I.N.D.A. V1…

Extruder blob

The blob (mass of plastic accumulated around the hotend) is one of the most scary-looking printing problems you might face with your 3D printer. Removing it after it happens is…

Squaring your MINI

During transport, assembly, or maintenance (like adjusting the belt tension) the printer can become slightly skewed, where one axis may not be perpendicular (90-degree angle) to…

Clogged nozzle/hotend (MINI/MINI+)

A clogged nozzle or hotend is a common issue for the FFF/FDM printers. If there are no issues, the filament is pushed in the hotend, melted, and then extruded through the nozzle.…

IR Filament Sensor Troubleshooting (MK2.5S, MK3S)

The IR sensor is a hybrid solution that combines an IR laser sensor triggered by a tiny mechanical lever. This means that in case one of the functions of the IR sensor is not working,…

Thermal Runaway (i3 series)

Thermal Runaway is a safety feature designed to cut power to the heaters in case of a thermistor malfunction. If your printer's thermistor would somehow dislodge itself, electronic…

Multimeter usage

In many cases, we need to decide whether a component is faulty or just wrongly installed. There are also situations where we need to decide exactly which component should be replaced.…

Warping

When printing large objects, you can sometimes run into an issue with the corners of the object being lifted from the bed – mostly when printing with high-temperature materials…

Firmware updating issues (MK2.5S/MK3S+/MMU2S/MMU3)

Flashing the firmware can sometimes fail, but most of the time it is nothing major. Before going deeper into issues related to flashing your printer, there are some initial steps…

Poor bridging

Bridging is a term for printing layers over thin air without the use of supports. It may sound like an impossible feat, but with our printers, it’s not that difficult. Keep in…

Filament Not Loading

If the filament is not loaded into the extruder, yet the printer is trying to pull the filament inside. It is usually a simple hardware problem, which we will fix in this article.  Ideal…

Print doesn't appear / Resin does not solidify

If the print does not appear on the printing platform, nor at the bottom of the resin tank, there are a couple of possible causes: Highly insufficient exposure times Old or separated…

Err: PRINT FAN ERROR

PRINT FAN ERROR error message occurs when the print fan (the one at the front of the extruder) does not receive any RPM (Revolutions per Minute) readings. This can be caused by…

Clogged nozzle (CORE One, CORE One L, XL, MK4/S, MK3.9/S)

A clogged nozzle is a possible issue for FFF/FDM printers. If there are no issues, the filament is pushed into the hotend, melted, and then extruded through the nozzle. However,…

IR filament sensor calibration (MMU3, MMU2S)

If you have the Original Prusa MMU2S or MMU3 installed in the MK3S/+ or MK3.5, the IR filament sensor needs to be calibrated before first use, in order to work properly. The calibration…

Factory reset (MK2S/MK2.5S/MK3S)

A factory reset can be used during troubleshooting to wipe configuration, calibration, and statistics data from your printer's memory. There are two ways how to perform a factory…

Layer separation and splitting FDM

This refers to the de-lamination of the printed layers. It is mostly caused by an incorrect preset/(custom)profile with wrong temperatures and/or too much cooling from either the…

Bad looking surface above supports

Generally speaking, it’s always the best option to rotate the object in such a way that the supports are not needed at all. However, if you need to print complex objects, you will…

Bed leveling failed

The Bed leveling failed error appears when there is something wrong with the last stage of the calibration. This calibration is the last step of XYZ calibration and is performed…

MMU2S LEDs meaning

As you can see, there are five main LEDs on the MMU2 unit. Their arrangement corresponds to the arrangement of the 5 PTFE tubes and 5 filament channels. Each LED consists of two…

Blown Fuse (MK3/MK3S/MK3S+)

The Original Prusa i3 MK3 series printers are equipped with fuses to protect their crucial components. If your printer or some of its components suddenly stopped working, it is…

Preheat error

The Preheat error message occurs when there is a problem with the preheat process before your print starts. Therefore, there is something preventing the printer from heating up…

Watertight prints

A print coming from molten plastic one might assume that it is water-tight, but that is not always the case. How to make an object look good and what makes it watertight does not…

Ghosting

Ghosting can be typically recognized by several waves that follow after a sharp edge of a model. An example can be seen in the photograph of 3DBenchy at the marked spot. How to…

Mintemp error bed #12207 (MINI)

What happened? The printer will display "Mintemp error" for the heatbed if the printer's heatbed temperature goes below 15 ºC at any point. In this case, the printer will stop…

Nextruder filament sensor (CORE One, CORE One L, MK4/S, MK3.9/S, XL/+)

The filament sensor equipped on our Nextruder printers detects the presence of a filament and filament run-out. The sensor is a Hall sensor, triggered by a mechanism composed of…

Filament failed to unload (MINI/MINI+)

When unloading the filament, the tip can have a large or irregular shape that is too big for the Bowden PTFE tube. You may hear some grinding sounds from the extruder as the printer…

Spaghetti monster

Why the name spaghetti monster? This print issue looks exactly like it sounds, a big mess of "spaghetti" on and around your print. It is actually extruded filament, which was misplaced…

SD card not working

Our Original Prusa i3 printers offer two ways of printing: via a USB cable or by loading g-codes from an SD card. If you are experiencing SD-card-related issues, try some of our…

MK3S keeps prompting filament change

With the Original Prusa MK3S (and the Original Prusa MK2.5S upgrade), we are introducing a completely reworked extruder with a new filament sensing system. It is a hybrid solution,…

Failing Z calibration (MK3S/MK2.5S)

The size of the extruder and the length of travel of the Z-axis is coded into the firmware. Therefore, if the assembly of the extruder, or the firmware for your extruder, is not…

Heatbed not heating up properly

If your Heatbed does not heat up, there are a couple of things you should check to identify the source of the issue. Temperature measurements Measuring the temperature with an…

Print fan is not spinning

The print fan is the fan blowing on the printed object, right below the nozzle. Depending on the material and where you are in the print it might not always spin at full speed…

MMU loading failed

If you see the error message “MMU load failed” on the printer’s LCD display, it indicates that the filament went through the Original Prusa MMU2S unit (registered by the F.I.N.D.A.…

FINDA setup and troubleshooting

The FINDA sensor, sometimes referred to as F.I.N.D.A. is essentially the MK2/S PINDA sensor (without thermistor), upcycled to be used as a filament sensor. It is triggered by the…

Connect Registration Failed

What happened?  During the configuration of Prusa Connect on the Original Prusa MINI/+, MK4/S, MK3.9/S, MK3.5/S or XL an error on this configuration can occur and the printer shows…

LCD screen not working

The LCD screen is vital for operating the printer. Should you encounter any kind of trouble, such as a dead screen, corrupted text, or other issues, please refer to the guide below.  First…

MAXTEMP

The MAXTEMP error occurs when at least one of the temperature readouts of the hotend is higher than 305 °C. It is a safety feature that prevents the printer from overheating uncontrollably. The…

Nozzle crashed into the heatbed

If this occurs it indicates a problem with the P.I.N.D.A. or SuperPINDA sensor. P.I.N.D.A. stands for Prusa INDuction Auto leveling. It is the Z-axis end-stop on the MK2/S and…

Please open idler and remove filament manually

The message on your LCD saying  Please open idler and remove filament manually shows up when the extruder motor does not succeed to remove the filament from the hotend/extruder.…

Vibration when printing (MK3S+/MK2.5S)

Your Original Prusa MK3S+/MK3S/MK3 printer may be causing some vibrations during use. In most cases, this will not cause any printing issues, however, we will show you how to minimize…

MMU needs user attention

If your MMU2S print encounters an issue it will stop mid-print and one or more of the LEDs will be blinking red. The following message will be displayed on the LCD: “MMU needs…

Stuck filament detection #31101 (CORE One) #35101 (CORE One L) #26101 (MK4S) #13101 (MK4) #27101 (MK3.9S) #21101 (MK3.9) #17108 (XL)

The Prusa CORE One, CORE One L, and the Original Prusa XL, MK4/S, MK3.9/S are equipped with a loadcell. Thanks to this component, starting from firmware 6.0.0, the printer can…

Err: EXTR. FAN ERROR

The EXTR. FAN ERROR message appears when the extruder fan does not receive any RPM (Revolutions per Minute) readings, in other words, there is something preventing it from spinning.…

Failing supports

Supports are an important part of a 3D-printed object, especially when printing a model with a complex shape. If support material breaks, it is likely to cause a failure on the…

PrusaLink Troubleshooting

This guide will help you solve the most common issues with the PrusaLink and Prusa Connect on your Original Prusa Printer. Original Prusa MK4/S, MK3.9/S, MK3.5/S, XL, MINI/+ Wi-Fi…

M.I.N.D.A./SuperPINDA sensor testing (MINI/MINI+)

The Induction auto-leveling sensor is a vital component facilitating the calibration of the MINI and MINI+. It acts like the Z end-stop and is the main component in mesh-bed leveling.…

Connect Registration Failed #31401 (CORE One) #35401 (CORE One L) #36401 (CORE One INDX) #17401 (XL) #26401 (MK4S) #13401 (MK4) #27401 (MK3.9S) #21401 (MK3.9) #28401 (MK3.5S) #23401 (MK3.5) #12401 (MINI)

What happened?  During the configuration of Prusa Connect on the Original Prusa Printers, an error can occur, and the printer shows the message "Registration to Prusa Connect failed…

Firmware in the internal flash corrupted! #12608 (MINI)

What happened? While flashing firmware to your printer an error might occur, and the screen will display the following message: "Firmware in the internal flash corrupted!". The…

Printer does not turn on or keeps turning off

If your printer doesn't turn on, keeps turning off, or is stuck in a boot loop, see here how to fix the issue. The printer must be powered off and disconnected from power when…

Hotend fan is not spinning

This issue can be preceded by the error Err: EXTR. FAN ERROR. Before we start checking your Hotend fan, power down and unplug your USB cable if it's connected. Open the electronics…

Thermal runaway print head #12204 (MINI)

What happened? The printer will display "Thermal runaway" for the print head if the printer drops the print head temperature by 6 ºC for a long period of time. This temperature…

Preheat error (Heatbed)

Preheat error can happen with either with your Nozzle or Heated bed. So 1st make sure with which of these you have the problem. "Heatbed preheat error" (Heatbed) Things to check: Make…

Factory reset (MMU2S pre firmware 1.0.6)

As the MMU unit has its own separate logic board, it also has its separate firmware that is cooperating with the printer firmware. This MMU-specific firmware is flashed directly…

Watchdog reset MINI

The "WATCHDOG reset" error message can appear on the display of the Original Prusa MINI if the system freezes or an operation crashes, for more than 4 seconds. This is a global…

Preheat error print head #12202 (MINI)

What happened? The message "Preheat error print head" is shown when the printer is unable to heat up the hotend more than 2 ºC for 20 seconds. The printer starts a safety feature,…

Broken supports (SL1/SL1S)

Broken supports (or missing parts of supports) are usually caused by incorrect settings in the PrusaSlicer. The supports are either too thin or the exposure time is set to a value…

IR Filament Sensor Troubleshooting (MINI/MINI+)

When purchasing the Original Prusa MINI+, kit or semi-assembled, there is an option to add a filament sensor to the printer. It can also be purchased separately later. This sensor…

Mintemp error print head #12208 (MINI)

What happened? The printer will display "Mintemp error" for the print head if the printer's hotend temperature goes below 15 ºC at any point. In this case, the printer will stop…

File incomplete. Continue anyway?

Our printers can detect a corrupted file on the SD card. The error message "File incomplete. Continue anyway?" occurs when there is a problem with the generated G-code and it could…

MMU MCU Error #04306 (MMU)

What happened? The Main Control Unit on the MMU control board has detected a power-related issue. How to fix it? Do not touch, move, connect, or disconnect any cables or electronic…

FINDA: Filament Stuck #04102 (MMU)

What happened? While the MMU unit was unloading a filament, the SuperFINDA sensor inside the selector stayed triggered/detecting a filament, while it shouldn’t.  The superFINDA…

Filament not loading (MK4/S, MK3.9/S)

If the filament is not loaded into the extruder, yet the printer is trying to pull the filament inside, there might be a hardware problem in some of the extruder components: we…

Load to extruder failed #04108 (MMU)

What happened? While loading into the extruder, the printer performs an automatic loading check as soon as the filament sensor detects a filament. If the check fails, this error…

Misaligned PINDA Sensor (MK2/S)

A misaligned P.I.N.D.A. Sensor is an issue that can be fixed by fine-tuning the printer. To do that, you need to calibrate the P.I.N.D.A. sensor position on multiple spots around…

Problems with infill

Various problems with infill are not the worst kind of trouble you may come across, however, in some cases it can put the structural integrity of your prints at risk. The ideal…

Homing error X #26304 (MK4S) #13304 (MK4) #27304 (MK3.9S) #21304 (MK3.9) #28304 (MK3.5S) #23304 (MK3.5)

What happened? The Original Prusa MK4/S, MK3.9/S, MK3.5/S displays the message: "Failed to home the extruder in X-axis, make sure there is no obstacle on X-axis". Error name: Homing…

First layer does not stick (SL1/SL1S)

If there is no object to be seen on the metal platform as it raises from the resin tank, it usually means that the first layer didn’t adhere properly to the platform. Let’s find…

Idler cannot home #04125 (MMU)

What happened? Before it can align with any of the filament positions, the Idler inside the MMU unit needs to be “homed” to determine its position. First, the Idler moves to one…

MMU2S Selector not moving

If the selector of your MMU2S upgrade is not moving smoothly, or if it cannot reach a certain position, the cause is usually one of the following issues: The selector blade is…

Factory reset (CORE One L, CORE One, MK4/S, MK3.9/S, MK3.5/S, MINI/+, XL)

During normal function, your printer saves statistics, calibration data, and personalized settings, even after it is turned off. If you feel like you changed settings that have…

Clogged hotend (XL)

A clogged nozzle or hotend is a common issue for FFF/FDM printers. If there are no issues, the filament is pushed in the hotend, melted, and then extruded through the nozzle. However,…

Preheat error bed #12201 (MINI)

What happened? A printer displaying the message "Preheat error bed" encountered an error while heating up the heatbed. If the heatbed temperature does not increase more than 2…

MMU2S idler unable to move freely

If your Original Prusa Multi Material idler barrel has some issues moving, makes clicking noises, or gives the error #04125 Idler cannot home, something is preventing the full…

Blown Fuse (MK2S/MK2.5/MK2.5S)

The Original Prusa i3 MK2 series printer is equipped with fuses to protect the most important peripheries. If your printer or some of its components suddenly stopped working, it…

TMC driver overtemp

This error refers to the TrinaMiC motor-drivers on the Einsy Rambo-board. They are the square chips located near the ports for the X, Y, Z, and E-motors on the Einsy RAMBo (Circled…

Print detached from supports (SL1/SL1S)

Why is this happening?  If the printed object detaches from its supports mid-print, it will fall into the resin tank, usually with the supports still attached to the printing platform.…

Hotend preheat error #31202 (CORE One) #35202 (CORE One L) #26202 (MK4S) #13202 (MK4) #27202 (MK3.9S) #21202 (MK3.9) 

What happened? The printer is showing the message "Hotend preheat error: Check the print head heater and thermistor wiring for potential damage" Error name: Hotend preheat error Error…

Bed preheat error #31201 (CORE One) #35201 (CORE One L) #36201 (CORE One INDX) #26201 (MK4S) #13201 (MK4) #27201 (MK3.9S) #21201 (MK3.9) #28201 (MK3.5S) #23201 (MK3.5) 

What happened? The printer is showing the message "Check the heatbed heater & thermistor wiring for possible damage." Error name: Bed preheat error Error code: #31201 (CORE One)…

FINDA didn't trigger #04101 (MMU)

What happened? During Filament loading, either to the MMU unit or to the Nozzle, if the filament does not reach the  SuperFINDA or is not detected, the printer will show an error. How…

Homing error Y #26305 (MK4S) #13305 (MK4) #21305 (MK3.9) #23305 (MK3.5)

What happened? The Original Prusa MK4S/MK4/MK3.9/MK3.5 displays the message: "Failed to home the Y-axis, make sure there is no obstacle on Y-axis". Error name: Homing error Y Error…

External SPI flash W25X20CL/xFLASH not responding - error

This occurs on some boards and its cause can be somewhat elusive. The W25X20CL is a memory chip on the Einsy Rambo board. It is an issue when flashing the firmware and is normally…

QR Error codes

This is an advanced system for displaying error screens, providing more useful information to the user. In case of an issue, the printer will display the name of the error followed…

Unload manually #04506 (MMU)

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…

Ambient temperature check (MK3/MK3S)

The Einsy board of your printer is equipped with an NTC thermistor, which is used to measure the surrounding ambient temperature. The sensor is located right above the main power…

Preheat the nozzle!

The error message Preheat the nozzle! occurs when you are loading new filament and the nozzle did not reach the needed temperature to do so. The minimum temperature for loading…

Removing and object stuck to the bottom of the tank

In case the first layer did not stick to the printing platform, it would remain stuck at the bottom of the tank. No matter how big or how small the stuck layer is, here is a quick…

Maxtemp error print head #12206 (MINI)

What happened? The printer will display "Maxtemp error" for the print head if the printer's hotend temperature goes 305 ºC at any point. This is a safety feature to prevent printer…

Factory reset (MINI)

Stored separately from the firmware itself, in the mainboard's EEPROM, you have statistics of your printer, calibration data related to the movement of the printer, and PID values…

Blown Fuse (MINI)

The Original Prusa MINI is equipped with a 24V Buddy mainboard. This 32-bit logic board has two removable automotive fuses protecting the crucial components. If your printer or…

Skewed / deformed prints (SL1/SL1S)

A skewed/deformed print is usually caused by loose screws – either the large black knob at the top of the cantilever, the screw(s) on the cantilever itself or the resin tank screws. Solution Cantilever…

Hotend mintemp error #31208 (CORE One) #35208 (CORE One L) #26208 (MK4S) #13208 (MK4) #27208 (MK3.9S) #21208 (MK3.9)

What happened? The printer is showing the message "Check the print head thermistor wiring for possible damage." Error name: Hotend mintemp error Error code: #31208 (CORE One) #35208…

Blackout occurred. Recover print?

The error message Blackout occurred. Recover print? appears if the power goes off for a longer period of time during printing, and the hotend and heatbed cool down. Therefore,…

Thermal runaway bed #12203 (MINI)

What happened? The printer will display "Thermal runaway" for the heatbed if the printer drops the heatbed temperature by 25 ºC for an extended period of time. A general temperature…

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)

What happened? The printer with the xBuddy board is equipped with a safety mechanism to detect power supply overcurrent situations in the Multi-material unit (MMU) connection.…

Visible layers (SL1/SL1S)

Even though SLA printers can achieve much better resolution than standard FFF/FDM 3D printers, layers on objects can be still visible if you look very closely. If you feel like…

Prints breaking away from the platform

The printing platform must be perfectly flat and degreased to ensure that the first prints are properly attached. If the pad or print itselfs separates from the printing platform,…

Homing error Z #31301 (CORE One) #35301 (CORE One L) #36301 (CORE One INDX) #26301 (MK4S) #13301 (MK4) #27301 (MK3.9S) #21301 (MK3.9)

What happened?  The printer is showing the message: "Failed to home the extruder in Z-axis, make sure the loadcell is working". Error name: Homing error Z Error code: #31301 (CORE…

Firmware update needed #04504 (MMU)

What happened? This error is shown when the MMU unit has an old or incompatible firmware version. The printer will show you an expected firmware version for the MMU unit. For example,…

Factory Reset (MMU)

This procedure is the same for the MMU3 and MMU2S units running firmware 3.0.0 or newer. In case you are running MMU2S with older FW, please go to Factory reset (MMU2S pre firmware…

Power Panic #36321 (INDX) #31321 (CORE One) #35321 (CORE One L) #26321 (MK4S) #13321 (MK4) #27321 (MK3.9S) #21321 (MK3.9) #28321 (MK3.5S) #23321 (MK3.5) 

What happened? The Original Prusa printers are equipped with a Power Panic feature. This feature can recover a print in case of a sudden power loss (read more about it here). The…

Holes in print (SL1/SL1S)

Large holes (defects) in printed objects are almost exclusively caused by dirt on the FEP foil or loose particles in the resin. Tiny pieces of debris on the bottom of the tank…

Scratches/bubbles on prints (SL1/SL1S)

Bubbles or small scratches (also appearing like cracks) on the object are caused by small pieces of dirt or debris in the tank (vat) you are using. These small objects travel in…

Loud noises from printer (SL1/SL1S)

When your printer emits loud noises, sounding like hammering onto sheet-metal. This can be caused by a firmware issue, or if resin has leaked into your printer through the tilt…

Maxtemp error bed #12205 (MINI)

What happened? The printer will display "Maxtemp error" for the heatbed if the printer's heatbed temperature goes above 110 ºC at any point. This is a safety feature to prevent…

Extruder preheat error #17202 (XL)

What happened? The message "Extruder preheat error: Check the heater and thermistor wiring for potential damage" is shown when the printer is unable to heat up the nozzle more…

De-lamination / separated layers (SL1/SL1S)

If you encounter de-lamination, separated layers, or missing layers, the cause is usually in a broken SL1/STL file. Another cause can be a faulty UV LED panel or dirt in the resin…

Connect Registration Failed #12401 (MINI)

What happened?  During the configuration of Prusa Connect on the Original Prusa MINI/+, an error on this configuration can occur and the printer shows the message "Registration…

Heatbed Port Overcurrent #31309 (CORE One) #35309 (CORE One L) #26309 (MK4S) #13309 (MK4) #27309 (MK3.9S) #21309 (MK3.9) #28309 (MK3.5S) #23309 (MK3.5) #12309 (MINI) #36309 (INDX)

What happened? Your printer is showing the message: "Overcurrent detected on xBuddy/Buddy heatbed port, disconnect the device." Error name: Heatbed Port Overcurrent Error code:…

Live Z adjust not saving

The Live Z Adjust is a tool that is used for easy corrections of the 1st three layers of your prints. In this article, we will look at the most common problem associated with it,…

Warped layers (SL1/SL1S)

Most resins have a tendency to shrink by several micrometers after they are cured. These expansions and resulting forces can lead to layer warping and layer separation. However,…

No file on USB #12604 (MINI/MINI+)

What happened? When flashing the firmware with the Alternative Method, you might get the text "Firmware file missing in the USB flash!". Error name: No file on USB Error code:…

Filament sensor didn't trigger #04103 (MMU)

What happened? If, during the filament load-to-nozzle process, the extruder's filament sensor is not triggered, the printer will display an error. How to fix it? Assembly Remake…

Missing parts (SL1/SL1S)

A print can finish even if some parts of the object weren’t printed fully, though a missing part of an object will more often cause the whole print-job to fail. Try printing a…

Connect Registration Failed #17401 (XL)

What happened?  During the configuration of Prusa Connect on the Original Prusa XL, an error on this configuration can occur and the printer shows the message "Registration to…

Selector cannot home #04115 (MMU)

What happened? Before it can align with any of the filament positions, the selector on the MMU unit needs to be “homed” to determine its position. For that, the selector moves…

Hotend thermal runaway #31204 (CORE One) #35204 (CORE One L) #26204 (MK4S) #13204 (MK4) #27204 (MK3.9S) #21204 (MK3.9)

What happened? The printer is showing the error "Hotend thermal runaway: Check the print head thermistor wiring for potential damage". Error name: Hotend thermal runaway  Error…

Object missing details

The Original Prusa SL1 3D printer can produce objects with an incredible amount of detail – tiny wrinkles on cloth of a figure, texture of skin, thin railings on buildings, etc.…

Nozzle Cleaning Failed #17834 (XL)

To achieve good quality prints, it is fundamental that the nozzle can make the right amount of contact with the print surface. In case this is not achieved, the printer will show…

Blown Fuse (MK4/S, MK3.9/S)

The Original Prusa MK4/S and MK3.9/S are equipped with a 24V xBuddy mainboard. This 32-bit logic board has three removable automotive fuses protecting the crucial components. If…

Saving log file (SL1/SL1S)

If you encounter an issue, we may request the log file from your Original Prusa SL1. This contains a wide range of info specific to your unit. By going to the printer menu to Settings…

SL1 Tilt-mechanism error

This error was changed in firmware version 1.5.0! This article only applies to SL1 printers with firmware older than 1.5.0. During the Wizard, the SL1 will test the tilting-motion…

Filament not loading (XL)

If the filament is not loaded into the extruder, yet the printer is trying to pull the filament inside, there might be a hardware problem in some of the extruder components: we…

Tilt homing failed #10101 (SL1/SL1S)

What happened? The printer is displaying the message: Tilt homing failed, check its surroundings, and repeat the action. Error name: Tilt homing failed Error code: #10101 Issued…

Resin sensor error #10307 (SL1/SL1S)

What happened? The printer displays the message: The resin sensor was not triggered. Check whether the tank and the platform are properly secured. Error name: Resin sensor error Error…

Filament sensor too early #04106 (MMU)

What happened? When loading the filament from the MMU to the extruder, the printer uses the extruder filament sensor to detect when the filament arrives in the extruder. Since…

Homing error Z #17301 (XL)

What happened? The printer displays the message "Failed to home the Z-axis, make sure the loadcell is working". Error name: Homing error Z Error code: #17301  How to fix it? Check…

Tower homing failed #10102 (SL1/SL1S)

What happened? The printer is displaying the message: Tower homing failed, make sure there is no obstacle in its path and repeat the action. Error name: Tower homing failed Error…

Firmware update failed #10534 (SL1)

What happened? The printer is displaying the message: The update of the firmware failed! Restart the printer and try again. Error name: Firmware update failed Error code: #10534 How…

Extruder thermal runaway #17204 (XL)

What happened? The printer will display "Extruder thermal runaway: Check the thermistor wiring for potential damage" if the temperature on the nozzle drops by 6 ºC for an extended…

Troubleshooting the MINI/MINI+ assembly

Filament sensor: Fil. stuck #04104 (MMU)

What happened? When the MMU unit unloads a filament from the extruder, the filament sensor inside the extruder should stop detecting the filament. In case it does not, this error…

Nozzle Cleaning Failed #31834 (CORE One) #35834 (CORE One L) #26834 (MK4S) #13834 (MK4) #27834 (MK3.9S) #21834 (MK3.9) #17834 (XL)

To achieve high-quality prints, the nozzle must make the correct amount of contact with the print surface. If this is not achieved, your printer will display the message "Nozzle…

Service menu - Individual Filament Calibration

Bed thermal runaway #31203 (CORE One) #35203 (CORE One L) #36203 (CORE One INDX) #26203 (MK4S) #13203 (MK4) #27203 (MK3.9S) #21203 (MK3.9) #28203 (MK3.5S) #23203 (MK3.5) 

What happened? The printer is showing the message "Check the heatbed thermistor wiring for possible damage." Error name: Bed thermal runaway  Error code: #31203 (CORE One) #35203…

Selftest failed (XL single-tool)

On the Original Prusa XL, the selftest checks for issues in the assembly of the printer, its wiring and the electronic components. It is the first part of the Calibration Wizard,…

Puppy error #17514 (XL)

What happened? On the Original Prusa XL, communication with the peripheral boards (e.g. Dwarf board) is achieved using the MODBUS protocol. In MODBUS, there are two types of devices:…

Homing Error #12301 (MINI)

What happened? During calibration, mesh bed leveling, or before a print, it is crucial for the printer firmware to determine the print head and heatbed position. This is done through…

Fan failure #10106 (SL1/SL1S)

What happened? The printer is displaying the message: Incorrect RPM reading of the fan. Please check its wiring and connection. Error name: Fan failure Error code: #10106 This…

I2C Send failed #31311 (CORE One) #35311 (CORE One L) #36311 (CORE One INDX) #26311 (MK4S) #13311 (MK4) #27311 (MK3.9S) #21311 (MK3.9) #28311 (MK3.5S) #23311 (MK3.5) #12311 (MINI/+)

What happened? On your Prusa Printer, the I2C bus is used for the xBuddy and Buddy boards to communicate with other printer components. If there is an error in sending data from…

Tool offset out of bounds #17104 (XL)

What happened? On the multi-tool versions of the Original Prusa XL, the offset of the tools compared to the first is calibrated through the Tool Offset Calibration. If the offset…

Temperature sensor failed #10205 (SL1/SL1S)

What happened? The printer is displaying the message: The Ambient temperature/UV LED temperature sensor failed. Error name: Temperature sensor failed Error code: #10205 The SL1…

Dock position out of bounds #17103 (XL)

What happened? The XL tool heads are connected to a metal profile on the back extrusion of the XL. During the selftest of the multi-tool head, the wizard will guide you through…

Invalid API key #10405 (SL1/SL1S)

What happened? The printer is displaying the message: Please turn on the HTTP digest (which is the recommended security option) or update the API key. You can find it in Settings…

Factory reset (SL1/SL1S)

Stored separately from the firmware itself, you have calibration data related to the operation of the printer and various statistics. If these values become corrupted or are not…

Display test failed #10120 (SL1/SL1S)

What happened? The printer is displaying the message: Display test failed, check the connection between the display and the A64 board. Error name: Display test failed Error code:…

Bed mintemp error #31207 (CORE One) #35207 (CORE One L) #36207 (CORE One INDX) #26207 (MK4S) #13207 (MK4) #27207 (MK3.9S) #21207 (MK3.9) #28207 (MK3.5S) #23207 (MK3.5)

What happened? The printer is showing  the message "Check the heatbed thermistor wiring for possible damage." Error name: Bed mintemp error  Error code: #31207 (CORE One) #35207…

Puppy error #17513 (XL)

What happened? On the Original Prusa XL, communication with the peripheral boards (e.g. Dwarf board) is achieved using the MODBUS protocol. In MODBUS, there are two types of devices:…

Expect overheating #10714 (SL1/SL1S)

What happened? The printer is displaying the message: Incorrect RPM reading of the fan. The print may continue, however, there's a risk of overheating. Warning name: Expect overheating Warning…

Status LED explained (MMU3)

This article is describing the status of the LEDs located on the multi material unit. Together there are five LEDs on the unit that correspond to the five available filament positions.  Attention:…

Fan RPM not in range #10122 (SL1/SL1S)

What happened? The printer is displaying the message: RPM of (fan)s not in range. Check if the fan is connected correctly. Error name: Fan RPM not in range Error code: #10122 Issued…

Modular bed error #17255 (XL)

What happened?  The printer is showing the message "Heatbed tile no. #: Unexpected temperature peak detected".  Error name: MB peak temp Error code: #17255 How to fix it?  A visual…

Unauthorized #10406 (SL1/SL1S)

What happened? The printer is displaying the message: The printer uses HTTP digest security. Please enable it also in your slicer (recommended), or turn off this security option…

Service menu - Factory Reset

Loadcell Timeout #31528 (CORE One) #35528 (CORE One L) #26528 (MK4S) #36528 (CORE One INDX) #13528 (MK4) #27528 (MK3.9S) #21528 (MK3.9)

What happened? The Prusa CORE One/+, CORE One L, and the Original Prusa MK4/S, MK3.9/S are equipped with a loadcell, which detects whether the nozzle is close enough to the steel…

I2C Receive Failed #31315 (CORE One) #35315 (CORE One L) #36315 (CORE One INDX) #26315 (MK4S) #13315 (MK4) #27315 (MK3.9S) #21315 (MK3.9) #28315 (MK3.5S) #23315 (MK3.5) #12315 (MINI/+)

What happened? On your Prusa Printer, the I2C bus is used for the xBuddy and Buddy boards to communicate with other printer components. If there is an error while the xBuddy board…

Extruder Mintemp error #17208 (XL)

What happened? The printer will display the message "Extruder Mintemp error: Check the thermistor wiring for potential damage" if the printer's nozzle temperature goes below 15…

Internal memory full #10516 (SL1/SL1S)

What happened? The printer displaying the message: Internal memory full, please delete some of your projects first. Error name: Internal memory full Error code: #10516 Projects…

USB drive not detected #10528 (SL1/SL1S)

What happened? The printer is displaying the message: No USB storage present Error name: USB drive not detected  Error code: #10528 How to fix it? The printer will copy the project…

MMU not responding #04401 (MMU)

What happened? The printer is trying to initiate communication with the MMU unit, but there is no response. How to fix it? Check the following: Make sure the MMU unit is present…

Unknown printer model #10323 (SL1/SL1S)

What happened? The printer is displaying the message: The printer model was not detected. Error name: Unknown printer model Error code: #10323 This error happens when the printer…

Nozzle Heater Overcurrent #31308 (CORE One) #35308 (CORE One L) #36308 (CORE One INDX) #26308 (MK4S) #13308 (MK4) #27308 (MK3.9S) #21308 (MK3.9)

What happened? The printer is showing the message: "Overcurrent detected on nozzle heater." Error name: Nozzle Heater Overcurrent Error code: #31308 (CORE One) #35308 (CORE One…

Pin not reached #17107 (XL)

What happened?  During the XYZ calibration, if the calibration pin is not reached, the printer is showing the message "Calibration pin has not been reached. Please check the pin…

Filament jam (MMU2S)

Speaker test failed #10310 (SL1/SL1S)

What happened? The printer is displaying the message: Speaker test failed, please check the connection and repeat the action. Error name: Speaker test failed Error code: #10310 The…

UV intensity too low #10318 (SL1/SL1S)

What happened? The printer is displaying the message: Requested intensity cannot be reached by max. allowed PWM Error name: UV intensity too low Error code: #10318 The most probable…

Tilt endstop not reached #10115 (SL1/SL1S)

What happened? The printer is displaying the message: Failed to reach tilt endstop, please check that the cable is connected and repeat the action. Error name: Tilt endstop not…

XY position invalid #17106 (XL)

What happened?  During XY probing, part of the Tool Offset calibration, if the offset in one of the tools is out of a range of acceptable values, the printer will show the message…

Ambient temperature too cold #10703 (SL1/SL1S)

What happened? The printer is displaying the message The ambient temperature is too low, the print can continue, but it might fail. Error name: Ambient temp. too cold Error code:…

No FW on USB #31604 (CORE One) #35604 (CORE One L) #36604 (CORE One INDX) #26604 (MK4S) #13604 (MK4) #27604 (MK3.9S) #21604 (MK3.9) #28604 (MK3.5S) #23604 (MK3.5) #17604 (XL) #12604 (MINI)

What happened? When flashing the firmware on your Original Prusa Printer, you might get the message "Firmware file missing in the USB flash!". Error name: No FW on USB flash drive Error…

Wrong printer model #10544 (SL1/SL1S)

What happened? The printer is displaying the message: This project was prepared for a different printer. Error name: Wrong printer model Error code: #10544  This error informs…

Resin too high #10109 (SL1/SL1S)

What happened? The printer is displaying the message: Measured resin volume [amount] ml is higher than required for this print. Make sure that the resin level does not exceed the…

Unexpected error #10501 (SL1/SL1S)

What happened? The printer is displaying the message: "An unexpected error has occurred. If print job is in progress, it should be finished. You can turn the printer off by pressing…

Loadcell Measure Failed #31526 (CORE One) #35526 (CORE One L) #36526 (CORE One INDX) #26526 (MK4S) #13526 (MK4) #27526 (MK3.9S) #21526 (MK3.9) #36526 (CORE One INDX)

What happened? The Prusa CORE One INDX, CORE One/+, CORE One L, and the Original Prusa MK4/S, MK3.9/S are equipped with a loadcell, which detects whether the nozzle is close enough…

Logging data over serial line (MMU2S)

Information from the data logged via serial line can be useful when doing advanced troubleshooting with your MMU2S unit or for providing it to Customer support when requested. To…

Tilt check failed #10119 (SL1/SL1S)

What happened? The printer is displaying the message: Tilt axis check failed! Check if the tilt can move smoothly in its entire range. Error name: Tilt check failed Error code:…

USB not connected #31602 (CORE One) #35602 (CORE One L) #36602 (CORE One INDX) #26602 (MK4S) #13602 (MK4) #27602 (MK3.9S) #21602 (MK3.9) #28602 (MK3.5S) #23602 (MK3.5) #17602 (XL) #12602 (MINI)

What happened? During firmware flashing on your Original Prusa Printer, you might get the message "USB drive not connected! Please insert a USB drive with a valid firmware file". Error…

Boost board problem #10320 (SL1S)

What happened? The printer is displaying the message: Communication with the Booster board failed. Error name: Boost board problem Error code: #10320 This error happens when the…

Unable to unload filament MMU1

Unsupported printer version #12611 (MINI/MINI+)

What happened? While flashing firmware to your printer an error might occur, and the screen will display the following message: "Firmware/printer versions do not match! You are…

XY probe unstable #17105 (XL)

What happened?  During XY probing, part of the Tool Offset calibration, if the same probes are not repeatable after multiple attempts, the printer will show the message "XY probing…

Parameters out of range #10707 (SL1/SL1S)

What happened? The printer is displaying the message: The print parameters are out of range of the printer, the system can try to fix the project. Proceed? Error name: Parameters…

Tower moving failed #10103 (SL1/SL1S)

What happened? The printer displaying the message: Moving the tower failed. Make sure there is no obstacle in its path and repeat the action. Error name: Tower moving failed Error…

Not connected to network #10402 (SL1/SL1S)

What happened? The printer is displaying the message: The printer is not connected to the internet, please check the connection in the Settings. Error name: Not connected to network Error…

Filament ejected #04507 (MMU)

What happened? The filament has been ejected to the front of the MMU unit, so that you can remove it. This feature is handy in case you are using the Spooljoin function. A depleted…

Firmware Update Required #31701 (CORE One) #35701 (CORE One L) #36701 (CORE One INDX) #26701 (MK4S) #13701 (MK4) #27701 (MK3.9S) #21701 (MK3.9) #28701 (MK3.5S) #23701 (MK3.5)

What happened? The Prusa CORE One, CORE One L, and the Original Prusa MK4/S, MK3.9/S, and MK3.5/S are equipped with the xBuddy board. Thanks to this, and the capability for firmware…

Puppy error #17516 (XL)

What happened? On the Original Prusa XL, communication with the peripheral boards (e.g. Dwarf board) is achieved using the MODBUS protocol. In MODBUS there are two types of devices,…

Invalid tilt align position #10121 (SL1/SL1S)

What happened? The printer is displaying the message: Invalid tilt alignment position. Error name: Invalid tilt align position Error code: #10121 How to fix it? Use the steps below…

Tower endstop not reached #10114 (SL1/SL1S)

What happened? The printer is displaying the message: Failed to reach tower endstop, please check that the tower motor is connected and repeat the action. Error name: Tower endstop…

Printer is not UV calibrated #10308 (SL1)

What happened? The printer displaying the message: The printer is not UV calibrated, please connect the UV calibrator and run the procedure. Error name: Printer is not UV calibrated Error…

Tower check failed #10118 (SL1/SL1S)

What happened? The printer is displaying the message: Tower axis check failed! Please check if the ball-screw can move smoothly in its entire range. Error name: Tower check failed  Error…

Internal error (DBUS mapping failed) #10507 (SL1/SL1S)

What happened? The printer displaying the message: Internal error (DBUS mapping failed), please restart the printer. Contact the support if the problem persists. Error name: Internal…

Remote API error #10407 (SL1/SL1S)

What happened? The printer is displaying the message: This request is not compatible with the Prusa remote API. See our documentation for more details. Error name: Remote API error Error…

General troubleshooting MMU1

UV LED temperature error #10209 (SL1/SL1S)

What happened? The printer is displaying the message: Reading of UV LED temperature has failed! This value is essential for the UV LED's lifespan and printer safety. Please contact…

Stuck Recovery (SL1/SL1S)

If the tilt platform is unable to tear away from the FEP foil during printing, this error will be presented. The printer will notice the increase current required to move the tilt…

Multi Material Post Processor Troubleshooting

Calibration error #10113 (SL1/SL1S)

What happened? The printer is displaying the message: The printer is not calibrated. Please run the Wizard first. Error name: Not mechanically calibrated Error code: #10113 Issued…

Not enough layers #10540 (SL1/SL1S)

What happened? The printer is displaying the message: The project must have at least one layer. Error name: Not enough layers Error code: #10540  This error happens when the project…

Precise Refinement Failed #31102 (CORE One) #35102 (CORE One L) #36102 (CORE One INDX) #17102 (XL)

What happened? If a Prusa Printer with a CoreXY detects a crash, it will attempt to find a reference point via a procedure called precise homing. If the right and left sides are…

Filament change #04508 (MMU)

What happened? This error happens when the filament change function is triggered. This can happen by: Filament change command in the printer’s menu. Issuing the M600 G-code command. The…

Tower position error #10123 (SL1/SL1S)

What happened? The printer is displaying the message: Tower not in the expected position. Are the platform and tank mounted and secured correctly? Error name: Tower position error Error…

Resin measuring failed #10124 (SL1/SL1S)

What happened? The printer is displaying the message: Measuring the resin failed. Check the presence of the platform and the amount of resin in the tank. Error name: Resin measuring…

File already exists! #10520 (SL1)

What happened? The printer displaying the message: File already exists! Error name: File already exists! Error code: #10520 When initiating a transfer of files to the printer,…

Loadcell Not Calibrated #31523 (CORE One) #35223 (CORE One L) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)

What happened? The Prusa CORE One/+, CORE One L, and the Original Prusa MK4/S, MK3.9/S are equipped with a loadcell, which detects whether the nozzle is close enough to the steel…

Project is corrupted #10541 (SL1/SL1S)

What happened? The printer is displaying the message: Opening the project failed. The file is corrupted. Please re-slice or re-export the project and try again. Error name: Project…

Homing error Y #31305 (CORE One) #35305 (CORE One L) #36305 (CORE One INDX) #17305 (XL)

What happened? The printer displays the message "Failed to home the Y-axis. Make sure there is no obstacle on the Y-axis." Error name: Homing error Y Error code: #31305 (CORE One)…

A64 Overheat #10207 (SL1/SL1S)

What happened? The printer is displaying the message: A64 temperature is too high. Measured: [temp] °C!. Error name: A64 Overheat Error code: #10207 This error is presented when…

Invalid FW size on USB #12603 (MINI/MINI+)

What happened? While flashing firmware to your printer an error might occur, and the screen will display the following message: "Firmware file has invalid size! Check the file…

Can't copy project #10704 (SL1/SL1S)

What happened? The printer is displaying the message: The internal memory is full, the project cannot be copied. You can continue printing - however, you must not remove the USB…

File not found #10518 (SL1/SL1S)

What happened? The printer displaying the message: Cannot find the selected file!  Error name: File not found Error code: #10518 General error when a file is not found. Possible…

UV led voltage error #10309 (SL1)

What happened? The printer displaying the message: UV LED voltages differ too much. The LED module might be faulty, please contact our support. Error name: UV led voltage error Error…

Ambient temperature too high #10702 (SL1/SL1S)

What happened? The printer is displaying the message: The ambient temperature is too high, the print can continue, but it might fail. Error name: Ambient temp. too hot Error code:…

Opening project failed #10504 (SL1/SL1S)

What happened? The printer displaying the message: Opening the project failed, the file is possibly corrupted. Please re-slice or re-export the project, try again. Error name:…

Fan warning #10713 (SL1/SL1S)

What happened? The printer is displaying the message: Incorrect RPM reading of the fan. Warning name: Fan warning Warning code: #10713 This warning is sent when the printer is…

Cleaning adaptor missing #10125 (SL1/SL1S)

What happened? The printer is displaying the message "Cleaning adaptor was not detected, it does not seem to be correctly attached to the print platform. Attach it properly and…

Power Panic #17321 (XL)

What happened? The Original Prusa XL is equipped with a Power Panic cable, which can recover the printer from a complete loss of power without needing batteries or an UPS. If the…

Another action is already running #10506 (SL1/SL1S)

What happened? The printer displaying the message: Another action is already running. Finish this action directly using the printer's touchscreen. Error name: Another action is…

Boot slot changed #10601 (SL1/SL1S)

What happened? The printer is displaying the message: The printer has booted from an alternative slot due to failed boot attempts using the primary slot. Update the printer with…

Unexpected MC error #10306 (SL1/SL1S)

What happened? The printer displaying the message: The motion controller has encountered an unexpected error, please restart the printer. Error name: Unexpected MC error Error…

Resin too low #10108 (SL1/SL1S)

What happened? The printer is displaying the message: Measured resin volume [amount] ml is lower than required for this print. Please refill the tank and restart the print. Error…

Not enough resin #10706 (SL1/SL1S)

What happened? The printer is displaying the message: The amount of resin in the tank is not enough for the current project. Adding more resin will be required during the print. Error…

Modular Bed Error #17319 (XL)

What happened? The Original Prusa XL can detect a power fault on the Modular Bed, with hardware measurements: in case this happens, the printer will show the message "Power failure". Error…

An unexpected error has occurred #10701 (SL1)

What happened? The printer displaying the message: An unexpected error has occurred. Please restart the printer. Contact our tech support if the problem persists. Error name: An…

Cannot read project #10539 (SL1/SL1S)

What happened? The printer is displaying the message: Opening the project failed. The file is possibly corrupted. Please re-slice or re-export the project and try again. Error…

Homing error X #17304 (XL)

What happened? The printer displays the message "Failed to home the X-axis, make sure there is no obstacle on X-axis or Y-axis." Error name: Homing error X Error code: #17304 The…

Toolchanger error #17135 (XL) #36135 (CORE One INDX)

What happened? The Original Prusa XL is showing the message "Check all tools if they are properly parked or picked". Error name: Toolchanger error Error code: #17135 (XL) #36135…

Disconnected UV LED panel #10321 (SL1/SL1S)

What happened? The printer is displaying the message: The UV LED panel is not detected. Error name: Disconnected UV LED panel Error code: #10321 This error is shown when the UV…

Directory not empty #10546 (SL1/SL1S)

What happened? The printer is displaying the message: The directory is not empty. Error name: Directory not empty Error code: #10546 This error is shown when you try to remove…

Cannot set update channel #10513 (SL1/SL1S)

What happened? The printer displaying the message: Cannot set the update channel, please restart the printer and try again. Error name: Cannot set update channel Error code: #10513 This…

This Wizard cannot be canceled #10522 (SL1/SL1S)

What happened? The printer displaying the message: This Wizard cannot be canceled, please finish the steps. Error name: This Wizard cannot be canceled Error code: #10522 Is not…

Failed to read the configuration file #10505 (SL1)

What happened? The printer displaying the message: Failed to read the configuration file. Try to reset the printer. If the problem persists, contact support. Error name: Failed…

ESP error #17505 (XL)

What happened? The printer is showing the message: "Command error" Error name: ESP command error Error code: #17505 On the Original Prusa XL, the XLBuddy board includes a WiFi…

EXTRUDER ERROR #17536 (XL)

What happened? The printer shows the message "Extruder motor is not spinning on tool #". In place of #, the number of the Dwarf board is shown.  This problem occurs due to increased…

Project analysis failed #10542 (SL1/SL1S)

What happened? The printer is displaying the message: Analysis of the project failed. Error name: Project analysis failed Error code: #10542 The printer can fail to analyze the…

ESP Error #31504 (CORE One) #35504 (CORE One L) #26504 (MK4S) #13504 (MK4) #27504 (MK3.9S) #21504 (MK3.9) #28504 (MK3.5S) #23504 (MK3.5) 

What happened? The printer is showing the message "Reading ESP firmware failed." Error name: ESP Error Error code: #31504 (CORE One) #35504 (CORE One L) #26504 (MK4S) #13504 (MK4)…

Resin low #10712 (SL1/SL1S)

What happened? The printer is displaying the message: Measured resin volume is too low. The print can continue, however, a refill might be required. Warning name: Resin low Warning…

Modular bed error #17250 (XL)

What happened?  In case the printer detects a problem with the modular bed, the display will show the following message: "Heatbed tile no. #: Damaged tile or wiring. Follow online…

USB flash drive not connected #17602 (XL)

What happened? During firmware flashing on your Original Prusa XL, you might get the message "USB drive not connected! Please insert a USB drive with a valid firmware file". Error…

Cannot remove project #10545 (SL1/SL1S)

What happened? The printer is displaying the message: Removing this project is not possible. The project is locked by a print job. Error name: Cannot remove project Error code:…

Serial number error #10527 (SL1/SL1S)

What happened? The printer is displaying the message: Serial numbers in wrong format! Please contact tech support! Error name: Serial number error  Error code: #10527 How to fix…

Heatbreak Mintemp error #17211 (XL)

What happened? The printer will display the message "Check the heatbreak thermistor wiring for possible damage" if the heatbreak temperature measures less than 5 °C at any point.…

Preload failed #10503 (SL1/SL1S)

What happened? The printer is displaying the message: Image preloader did not finish successfully! Error name: Preload failed Error code: #10503 This error shows that the printer…

Printer Variant Mismatch #10711 (SL1/SL1S)

What happened? The printer is displaying the message: The model was sliced for a different printer variant [SL1/SL1S]. Your printer variant is [SL1S/SL1]. Warning name: Printer…

Multiplexer

UV intensity too high #10317 (SL1/SL1S)

What happened? The printer is displaying the message: Requested intensity cannot be reached by min. allowed PWM. Error name: UV intensity too high  Error code: #10317 The most…

Filament pulleys MMU1

Mask noavail warning #10709 (SL1/SL1S)

What happened? The printer is displaying the message: Print mask is missing. Error name: Mask no avail warning Error code: #10709 This error shows when the print mask part of the…

Object cropped warning #10710 (SL1/SL1S)

What happened? The printer is displaying the message: Object was cropped because it does not fit the print area. Warning name: Object cropped warning Warning code: #10710 This…

Data preparation failure #10525 (SL1/SL1S)

What happened? The printer is displaying the message: Failed to serialize Wizard data. Restart the printer and try again. Error name: Data preparation failure Error code: #10524 How…

Temperature out of range #10208 (SL1/SL1S)

What happened? The printer is displaying the message: (sensor)s not in range! Measured temperature: (temperature). Keep the printer out of direct sunlight at room temperature (18…

Incorrect printer model #10705 (SL1/SL1S)

What happened? The printer is displaying the message: The model was sliced for a different printer model, please reslice. Error name: Printer model mismatch warning Error code:…

Broken UV LED panel #10322 (SL1S)

What happened? The printer is displaying the message: A part of the LED panel is disconnected. Error name: Broken UV LED panel Error code: #10322 This error shows that part of…

FW in internal flash corrupted #31608 (CORE One) #35608 (CORE One L) #36608 (CORE One INDX) #26608 (MK4S) #13608 (MK4) #27608 (MK3.9S) #21608 (MK3.9) #28608 (MK3.5S) #23608 (MK3.5) #17608 (XL) #12608 (MINI)

What happened? When trying to flash the firmware on your Original Prusa Printer, it shows the error: "Firmware in the internal flash corrupted! Please reflash the firmware." Error…

Heatbreak MAXTEMP Error #31212 (CORE One) #35212 (CORE One L) #26212 (MK4S) #13212 (MK4) #27212 (MK3.9S) #21212 (MK3.9) 

What happened? The printer is showing the message "Check the heatbreak thermistor wiring for possible damage." Error name: Heatbreak MAXTEMP Error Error code: #31212 (CORE One)…

Colour bleeding

Cannot get update channel #10514 (SL1)

What happened? The printer displaying the message: Cannot get the update channel, please restart the printer and try again. Error name: Cannot set update channel Error code: #10514 This…

UV LED calibrator not detected #10311 (SL1)

What happened? The printer is displaying the message: The UV LED calibrator is not detected. Check the connection and try again. Error name: UV LED calibrator not detected Error…

UV calibration error #10319 (SL1)

What happened? The printer is displaying the message: Correct settings were found, but the standard deviation (found) is greater than the allowed value (allowed). Verify the UV…

Wrong revision of motion controller #10301 (SL1)

What happened? The printer displaying the message: Wrong revision of the motion controller. Please replace it or contact our support. Error name: Wrong revision of motion controller Error…

UV LED heatsink overheating #10206 (SL1)

What happened? The printer displaying the message: UV LED is overheating! Check whether the heatsink is installed correctly. Error name: UV LED heatsink overheating  Error code:…

Bed maxtemp error #31205 (CORE One) #35205 (CORE One L) #36205 (CORE One INDX) #26205 (MK4S) #13205 (MK4) #27201 (MK3.9S) #21201 (MK3.9) #28201 (MK3.5S) #23201 (MK3.5)

What happened? The printer shows the error "Check the heatbed thermistor wiring for possible damage." Error name: Bed Maxtemp error  Error code: #31205 (CORE One) #35205 (CORE…

Connect Registration Failed #23401 (MK3.5)

What happened?  During the configuration of Prusa Connect on the Original Prusa MK3.5, an error on this configuration can occur and the printer shows the message "Registration…

Download failed #10404 (SL1/SL1S)

What happened? The printer is displaying the message: The download failed. Check the connection to the internet and try again. Error name: Download failed Error code: #10404 How…

Modular bed error #17257 (XL)

What happened?  Before starting each print, your Original Prusa XL will test the resistance of the heatbed tile, by heating it and measuring its current. In case of an issue related…

Calibration load failed #10524 (SL1)

What happened? The printer is displaying the message: Failed to load fans and LEDs factory calibration. The printer was not able to find the UV PMW value due to a calibration error,…

Loadcell Bad Configuration #31527 (CORE One) #35527 (CORE One L) #36527 (CORE One INDX) #26527 (MK4S) #13527 (MK4) #27527 (MK3.9S) #21527 (MK3.9)

What happened? The Prusa CORE One/+, CORE One L, and the Original Prusa MK4/S, MK3.9/S are equipped with a loadcell, which detects whether the nozzle is close enough to the steel…

Hotend preheat error #28202 (MK3.5S) #23202 (MK3.5)

What happened? The printer is showing the message "Hotend preheat error: Check the print head heater and thermistor wiring for potential damage" Error name: Hotend preheat error Error…

UV data error #10533 (SL1)

What happened? The printer is displaying the message: Data is from unknown UV LED sensor! Error name: UV data error Error code: #10533 After calibration using the UV calibrator,…

No file to reprint #10508 (SL1)

What happened? The printer displaying the message: Error, there is no file to reprint. Error name: No file to reprint Error code: #10508 This error is displayed in case of a reprint…

Display usage error #10535 (SL1)

What happened? The printer is displaying the message: Display usage error. The display has just been replaced or a factory reset has been performed, clearing the usage data. Error…

Unsupported firmware BBF file #17614 (XL)

What happened? While flashing firmware to your Original Prusa XL, an error might occur, and the screen will display the following message: "USB flash drive contains unsupported…

Data overwrite failed #10530 (SL1/SL1S)

What happened? The printer is displaying the message: Saving the new factory default value failed. Restart the printer and try again. Error name: Data overwrite failed Error code:…

Hostname error #10536 (SL1/SL1S)

What happened? The printer is displaying the message: Failed to set hostname Error Name: Hostname error Error code: #10536 How to fix it? The Hostname set up on your printer does…

Emergency stop #31510 (CORE One) #35510 (CORE One L) #36510 (CORE One INDX) #26510 (MK4S) #13510 (MK4) #17510 (XL) #27510 (MK3.9S) #21510 (MK3.9) #28510 (MK3.5S) #23510 (MK3.5) #12510 (MINI)

What happened? The Original Prusa Printers is showing the message: "Emergency stop invoked by G-code (M112)". Error name: Emergency stop Error code: #31510 (CORE One) #35510 (CORE…

UV LED calibrator error #10314 (SL1)

What happened? The printer is displaying the message: The UV LED calibrator detected some light on a dark display. This means there is a light 'leak' under the UV calibrator, or…

UV LED calibrator link error #10313 (SL1)

What happened? The printer is displaying the message: Communication with the UV LED calibrator has failed. Check the connection and try again. Error name: UV LED calibrator link…

Hotend thermal runaway #28204 (MK3.5S) #23204 (MK3.5)

What happened? The printer is showing the message "Hotend thermal runaway: Check the print head thermistor wiring for possible damage." Error name: Hotend thermal runaway Error…

UV LED calibrator readings error #10315 (SL1)

What happened? The printer is displaying the message: The UV LED calibrator failed to read expected UV light intensity. Check the UV calibrator placement on the screen. Error name:…

No UV calibration data #10532 (SL1)

What happened? The printer is displaying the message: No calibration data to show! UV calibration needs to be remade. Error name: No UV calibration data Error code: #10532 How…

Wizard data failure #10526 (SL1/SL1S)

What happened? The printer is displaying the message: Failed to save Wizard data. Restart the printer and try again. Error name: Wizard data failure Error code: #10526 How to fix…

Calibration project is invalid #10543 (SL1/SL1S)

What happened? The printer is displaying the message: Calibration project is invalid. Error name: Calibration project is invalid Error code: #10543 This error is shown when the…

UV LED calibrator connection error #10312 (SL1)

What happened? The printer is displaying the message: Cannot connect to the UV LED calibrator. Check the connection and try again. Error name: UV LED calibrator connection error Error…

Marlin Request Timeout #31530 (CORE One) #35530 (CORE One L) #36530 (CORE One INDX) #26530 (MK4S) #13530 (MK4) #27530 (MK3.9S) #21530 (MK3.9) #28530 (MK3.5S) #23530 (MK3.5)

What happened? The Original Prusa Printers can manage several tasks simultaneously: this is called multithreading. In case of an issue related to multithreading, the printer will…

Heatbreak MINTEMP Error #31211 (CORE One) #35211 (CORE One L) #26211 (MK4S) #13211 (MK4) #27211 (MK3.9S) #21211 (MK3.9)

What happened? The printer is showing the message "Check the heatbreak thermistor wiring for possible damage." Error name: Heatbreak MINTEMP Error Error code: #31211 (CORE One)…

Tangled filament

A tangled filament spool can cause a print to fail, as a knot can form on the filament strand. This is caused by letting the filament end go, for example during a filament unloading,…

Loadcell not calibrated #17523 (XL)

What happened? The Original Prusa XL is equipped with a loadcell, to detect that the nozzle is close enough to the steel sheet for printing, and to avoid damage that would be caused…

Print examples missing #10523 (SL1/SL1S)

What happened? The printer is displaying the message: Examples (any projects) are missing in the user storage. Redownload them from the "Settings" menu. Error name: Print examples…

Modular bed error #17303 (XL)

What happened?  The printer is showing the message: "Unexpected invalid current".  Error name: MB invalid current Error code: #17303 An LED on the Modular Bed lights up when this…

Puppy error #17521 (XL)

What happened? On the Original Prusa XL, communication with the peripheral boards (e.g. Dwarf board) is achieved using the MODBUS protocol. In MODBUS, there are two types of devices:…

I2C Send Failed #17311 (XL)

What happened? On the Original Prusa XL, the I2C bus is used for the XLBuddy to communicate with other printer components. If there is an error in sending data from the XLBuddy,…

Hotend maxtemp error #31206 (CORE One) #35206 (CORE One L) #26206 (MK4S) #13206 (MK4) #27206 (MK3.9S) #21206 (MK3.9) #28206 (MK3.5S) #23206 (MK3.5)

What happened? The printer is showing the message "Check the print head thermistor wiring for possible damage." Error name: Hotend Maxtemp error Error code: #31206 (CORE One) #35206…

MCU Maxtemp Error #31213 (CORE One) #35213 (CORE One L) #26213 (MK4S) #13213 (MK4) #27213 (MK3.9S) #21213 (MK3.9) #17213 (XL) #12213 (MINI/+)

What happened?  If the thermistor integrated into one of the electronic boards measures a temperature above 100 °C at any point, the printer will stop and show the message "MCU…

Out of Memory #31507 (CORE One) #35507 (CORE One L) #26507 (MK4S) #13507 (MK4) #27507 (MK3.9S) #21507 (MK3.9) #28507 (MK3.5S) #23507 (MK3.5) #31507 (CORE One)

What happened? The Original Prusa Printers' electronic boards have memory, including RAM (Random Access Memory). In rare cases, the RAM can be fully consumed, with the printer…

Modular bed error #17256 (XL)

What happened?  If your Original Prusa XL fails to heat correctly one of the heatbed tiles, the printer will show the message "Heatbed tile no. #: Preheat error".  Error name:…