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                  1. Support
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                  3. 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) 
                   

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                  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) 

                  Relevant for

                  INDX family
                  CORE One family
                  MK4 family
                  MK3.5 family
                  MK3.9 family
                  16 comments
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                  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) #35201 (CORE One L) #36201 (CORE One INDX) #26201 (MK4S) #13201 (MK4) #27201 (MK3.9S) #21201 (MK3.9) #28201 (MK3.5S) #23201 (MK3.5) 

                  This message is shown when, during the preheat, the printer does not increase more than 2 ºC for 20 seconds. The heating is paused so the issue can be fixed.

                  How to fix it?

                  CORE One L

                  Do not access or remove panels or disassemble components on the heatbed and surrounding parts, including cables, as this can pose a safety risk due to electronics. 
                  Report the issue to our 24/7 technical support, and we will guide you through the next steps. 

                  CORE One, MK4/S, MK3.9/S, MK3.5/S

                  Make sure that the ambient temperature where the printer is is stable, and above 18 ºC.

                  This error can be caused by damage to either the heatbed thermistor or the heatbed power cable.

                  Doing regular maintenance on the printer may prevent this type of issue.

                  On the heatbed, check the following:

                  • See if the thermistor is firmly seated below the Golden Kapton tape.
                  • Make sure that the washer is screwed above the round cable connector, not below it.
                  • Check if the M3nN nut is holding the screw firmly.
                  • Access the xBuddy board. Check the heatbed power cable, the heatbed thermistor, and the fuse that protects the heatbed.

                  In case all the items are correct, there might be an internal break in one of the cables. If you do not have a multimeter, it is possible to check the cables using the following test: 

                  1. Use a hairdryer to blow hot air at the heatbed.
                  2. While doing that, check if there is any temperature change on the LCD screen.
                  3. If there is a positive temperature change it means that the heatbed thermistor is working. In this case, the heater is defective.
                  4. If there is no change at all, the heatbed thermistor is defective.

                  Multimeter check

                  In case you have a multimeter available, it is possible to check the resistance of the cables using the Multimeter usage guide.

                  Was this article helpful?
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                  Topics

                  • Troubleshooting
                    • Printer troubleshooting
                      • Spaghetti monster
                      • Extruder blob
                      • Clogged nozzle/hotend (MK3.5/S, MK3S+, MK2.5S)
                      • Extruder noises
                      • Multimeter usage
                      • PrusaLink Troubleshooting
                      • Toolchanger error #17135 (XL) #36135 (CORE One INDX)
                      • 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) 
                      • Hotend preheat error #31202 (CORE One) #35202 (CORE One L) #26202 (MK4S) #13202 (MK4) #27202 (MK3.9S) #21202 (MK3.9) 
                      • 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) 
                      • Hotend thermal runaway #31204 (CORE One) #35204 (CORE One L) #26204 (MK4S) #13204 (MK4) #27204 (MK3.9S) #21204 (MK3.9)
                      • Hotend mintemp error #31208 (CORE One) #35208 (CORE One L) #26208 (MK4S) #13208 (MK4) #27208 (MK3.9S) #21208 (MK3.9)
                      • 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)
                      • 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)
                      • 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)
                      • Homing error Y #31305 (CORE One) #35305 (CORE One L) #36305 (CORE One INDX) #17305 (XL)
                      • 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)
                      • 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)
                      • 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/+)
                      • Loadcell Not Calibrated #31523 (CORE One) #35223 (CORE One L) #26523 (MK4S) #13523 (MK4) #27523 (MK3.9S) #21523 (MK3.9)
                      • Loadcell Tare Error #31524 (CORE One) #35524 (CORE One L) #26524 (MK4S) #13524 (MK4) #27524 (MK3.9S) #21524 (MK3.9)
                      • Loadcell Tare Failed #31525 (CORE One) #35525 (CORE One L) #26525 (MK4S) #13525 (MK4) #27525 (MK3.9S) #21525 (MK3.9)
                      • 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)
                      • Loadcell Bad Configuration #31527 (CORE One) #35527 (CORE One L) #36527 (CORE One INDX) #26527 (MK4S) #13527 (MK4) #27527 (MK3.9S) #21527 (MK3.9)
                      • Loadcell Timeout #31528 (CORE One) #35528 (CORE One L) #26528 (MK4S) #36528 (CORE One INDX) #13528 (MK4) #27528 (MK3.9S) #21528 (MK3.9)
                      • Heatbreak MINTEMP Error #31211 (CORE One) #35211 (CORE One L) #26211 (MK4S) #13211 (MK4) #27211 (MK3.9S) #21211 (MK3.9)
                      • Heatbreak MAXTEMP Error #31212 (CORE One) #35212 (CORE One L) #26212 (MK4S) #13212 (MK4) #27212 (MK3.9S) #21212 (MK3.9) 
                      • Blown Fuse (MK4/S, MK3.9/S)
                      • Filament not loading (MK4/S, MK3.9/S)
                      • Homing error Y #26305 (MK4S) #13305 (MK4) #21305 (MK3.9) #23305 (MK3.5)
                      • Tangled filament
                      • Nextruder filament sensor (CORE One, CORE One L, MK4/S, MK3.9/S, XL/+)
                      • Connect Registration Failed
                      • Hotend maxtemp error #23206 (MK3.5)
                      • Connect Registration Failed #21401 (MK3.9)
                      • Connect Registration Failed #23401 (MK3.5)
                      • Homing Error Z #23301 (MK3.5)
                      • Nozzle Heater Overcurrent #23308 (MK3.5)
                      • Blue Screen of Death (BSOD) #31538 (CORE One) #35538 (CORE One L) #36538 (CORE One INDX) #26538 (MK4S) #13538 (MK4) #27538 (MK3.9S) #17538 (XL) #21538 (MK3.9) #28538 (MK3.5S) #23538 (MK3.5) #12538 (MINI)
                      • Stuck filament detection #31101 (CORE One) #35101 (CORE One L) #26101 (MK4S) #13101 (MK4) #27101 (MK3.9S) #21101 (MK3.9) #17108 (XL)
                      • Heatbed temp not matching #31209 (CORE One) #35209 (CORE One L) #26209 (MK4S) #13209 (MK4) #27209 (MK3.9S) #21209 (MK3.9) #28209 (MK3.5S) #23209 (MK3.5)
                      • Hotend temp not matching #31210 (CORE One) #35210 (CORE One L) #26210 (MK4S) #13210 (MK4) #27210 (MK3.9S) #21210 (MK3.9)
                      • Under-extrusion (Nextruder printers)
                      • Nozzle Timeout #31819 (CORE One) #35819 (CORE One L) #36819 (CORE One INDX) #26819 (MK4S) #13819 (MK4) #27819 (MK3.9S) #21819 (MK3.9) #28819 (MK3.5S) #23819 (MK3.5) #17819 (XL) #12819 (MINI)
                      • Uneven bed #31111 (CORE One) #35111 (CORE One L) #36111 (CORE One INDX)
                      • Filament sensor stuck #31113 (CORE One) #35113 (CORE One L) #36113 (CORE One INDX) #17113 (XL) #26113 (MK4S) #13113 (MK4) #27113 (MK3.9S) #21113 (MK3.9) #28113 (MK3.5S) #23113 (MK3.5) #12113 (MINI/+)
                      • Chamber MAXTEMP error #31214 (CORE One) #35214 (CORE One L) #36214 (CORE One INDX)
                      • Homing error X #31304 (CORE One) #35304 (CORE One L) #36304 (CORE One INDX) #17304 (XL)
                      • Puppy error #31511 (CORE One) #35511 (CORE One L) #36511 (CORE One INDX)
                      • Puppy error #31513 (CORE One) #35513 (CORE One L) #36513 (CORE One INDX)
                      • Fil. sensor troubleshooting #31114 (CORE One) #26114 (MK4S) #13114 (MK4) #27114 (MK3.9S) #21114 (MK3.9) #28114 (MK3.5S) #23114 (MK3.5)
                      • Chamber Mintemp error #31215 (CORE One) #35215 (CORE One L) #36215 (CORE One INDX)
                      • MCU in Buddy is overheated #31825 (CORE One) #35825 (CORE One L) #26825 (MK4S) #27825 (MK3.9S) #28825 (MK3.5S) #13825 (MK4) #21825 (MK3.9) #23825 (MK3.5) #17825 (XL) #12825 (MINI)
                      • The heatbed cooled down during the power outage #31808 (CORE One) #35808 (CORE One L) #26808 (MK4S) #27808 (MK3.9S) #28808 (MK3.5S) #13808 (MK4) #21808 (MK3.9) #23808 (MK3.5) #17808 (XL) 
                      • The G-code isn't fully compatible #31803 (CORE One) #26803 (MK4S) #27803 (MK3.9S) #28803 (MK3.5S) #13803 (MK4) #21803 (MK3.9) #23803 (MK3.5) #17803 (XL) #12803 (MINI)
                      • Filament not detected #31804 (CORE One) #35804 (CORE One L) #26804 (MK4S) #27804 (MK3.9S) #28804 (MK3.5S) #13804 (MK4) #21804 (MK3.9) #23804 (MK3.5) #17804 (XL) #12804 (MINI)
                      • Print preview unfinished selftest #31801 (CORE One) #35801 (CORE One L) #26801 (MK4S) #27801 (MK3.9S) #28801 (MK3.5S) #13801 (MK4) #21801 (MK3.9) #23801 (MK3.5) #17801 (XL) #12801 (MINI)
                      • Crash recovery axis long #31809 (CORE One) #35809 (CORE One L) #26809 (MK4S) #13809 (MK4) #27809 (MK3.9S) #21809 (MK3.9) #28809 (MK3.5S) #23809 (MK3.5) #17809 (XL) #12809 (MINI)
                      • Crash recovery repeated crash #31811 (CORE One) #35811 (CORE One L) #26811 (MK4S) #13811 (MK4) #27811 (MK3.9S) #21811 (MK3.9) #28811 (MK3.5S) #23811 (MK3.5) #17811 (XL) #12811 (MINI)
                      • Crash recovery axis short #31810 (CORE One) #35810 (CORE One L) #26810 (MK4S) #13810 (MK4) #27810 (MK3.9S) #21810 (MK3.9) #28810 (MK3.5S) #23810 (MK3.5) #17810 (XL) #12810 (MINI)
                      • Crash recovery home fail #31812 (CORE One) #35812 (CORE One L) #26812 (MK4S) #13812 (MK4) #27812 (MK3.9S) #21812 (MK3.9) #28812 (MK3.5S) #23812 (MK3.5) #17812 (XL) #12812 (MINI)
                      • Loading obstruction #31119 (CORE One) #35119 (CORE One L) #17119 (XL)
                      • Homing calibration needed #31118 (CORE One) #35118 (CORE One L) #36118 (CORE One INDX)#17118 (XL)
                      • Calibrate homing from menu #31120 (CORE One) #35120 (CORE One L) #36120 (CORE One INDX) #17120 (XL)
                      • MCU overheat #35270
                      • PCB overheat #35271
                      • Data Timeout #35330
                      • AC Controller Fault #35273
                      • AC controller fault #35333 (CORE One L)
                      • AC controller fault #35335 (CORE One L)
                      • AC controller fault #35336 (CORE One L)
                      • Selftest failed (CORE One L)
                      • Bed fan is not spinning #35849 (CORE One L)
                      • PSU fan is not spinning #35850 (CORE One)
                      • Nozzle tool remains attached to the print head (CORE One INDX)
                      • Selftest failed (CORE One/+)
                      • Clogged nozzle (CORE One, CORE One L, XL, MK4/S, MK3.9/S)
                      • Adjusting belt tension (CORE One/+, CORE One INDX, CORE One L/+)
                      • SD cards and USB drives
                    • Print Quality Troubleshooting
                    • QR Error codes
                    • Print Error Messages

                  11 comments

                  Log in  to post a comment
                  morryprints
                  •
                  Found the problem was insufficiently tightened screws on the M3 terminal screws (despite them appearing ok at first glance). I must state however they were moderately tight and the printer has worked fine for 12+ months.
                  The problem has only seemed to arise after i did a hot ABS print for the first time-indicating that thermal cycling loosened the screws. A remedy to this would be adding spring washers which I intend to do. You need to remove the torx screws on the bed to lift it up and access the nylocs on the other side of the heatbed to tighten. Only takes a couple of mins with the right tools.
                  Reply
                  TallTeacherGuy
                  •
                  My new MK4S has been going well so this error is quite surprising. The only thing I did different in the error producing print was 'goose' the heated bed with a hair dryer to speed its get-up-to-temp, stopping when the reading was 95 out of the 100 degree target. The print, a small one, got half way before stopping dead in tracks with the error. There's no getting out other than using Control to raising the extruder and then turning off power.
                  Could it have been my hair dryer/impatience?
                  Reply
                  snafu
                  •
                  READ BEFORE attempting to fix the error!

                  The error-message is quite misleading, so here are a few hints that might save you a lot of time for troubleshooting!

                  1. Is it a SMALL object you are trying to print?
                  If so, chances are you get a false-positive error warning! There are some answers right here about this problem, so I'll keep it short: Try to reduce cooling (often times your heat-end cooler simply works too good for very small objects (in my case 10x10x10 mm)).
                  Try to print a larger print first - if you do not get the error then, chances are you suffer this exact type of error.

                  2. Before checking the heatbed cables, check your thermistor - because you can do this with everything assembled!
                  Take a heatgun or hairdryer, and start the printer. As soon as you see the heatbed temperature in the display start the heatgun. If the value changes within a reasonable amount, you almost certainly can rule out the thermistor.

                  3. Next look at your heatbed cables. You can check two things without disassembling too much:
                  a) are the red and black wire connected properly?
                  b) is the thermistorcable connected properly? Are all three cables firm and tight? Give the thermistor a careful pull - if it doesn't move, you're good to go.

                  Usually one of the elements under 1 to 3 is the culprit. If not, there is always the chance something on the xBuddy-Board might be broken.
                  Reply
                  Mrfloop
                  •
                  Pretty sure my problem was the red / black connectors to the head bed weren't tightened all the way.

                  It's possible I was too delicate with them during the initial build. Another possibility, is that the table my printer was on originally was wobbly. Might have rattled the screw loose.

                  Regardless, cranking down those two connectors (which unfortunately required unscrewing the heat bed, and having my wife clamp the nut in place while I tightened, very difficult!) seems to have fixed the problem. 2 hours into a 3.5 hour PLA print with no error codes thrown my way.
                  Reply
                  HarryLasVegas
                  •
                  That was my problem, thanks for pointing me in this direction.
                  Reply
                  AndyS
                  •
                  New kit CoreOne.
                  Doing the automatic calibration, the bed heats up then faults out.
                  I manually ran the bed up to 120. It got there, held, and followed temp set points back down.

                  The thermistor and heater work.

                  The problem seems like the speed of changing temp.

                  Ideas or solutions?
                  Reply
                  John
                  •
                  Hello, did you found out the solution ?
                  Reply