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                  1. Support
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                  3. Printer troubleshooting
                  4. MCU overheat #35270
                   

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                  MCU overheat #35270

                  Relevant for

                  CORE One L
                  CORE One L+
                  1 comment
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                  What happened? 

                  The Modular Bed Control Unit (MCU) monitors temperature to ensure the printer operates within safe limits. When the internal temperature exceeds a defined threshold, the printer displays a warning "Microcontroller unit of %s is overheating", where in place of %s, the name of the component is shown. 

                  Error name: MCU Overheat

                  Error code: #35270

                  How to fix it? 

                  This warning typically appears when the ambient temperature around the printer is too high, or when the printer is enclosed without proper ventilation. 

                  • Ensure the printer is used in an environment with ambient temperature below 30 °C (86 °F).
                  • Allow the printer to cool down: turn it off and let it rest for at least 10–15 minutes before continuing.
                  • Minimize continuous long-duration prints at high bed temperatures, especially in warm environments.

                  If the issue persists even in a cool environment, contact our Support for further diagnostics, as the internal sensors or electronics may be faulty. 

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                  1 comment

                  Log in  to post a comment
                  bryn51
                  •
                  This beggars belief.
                  Its not that the temp is too high, its that the componentry is not tolerating what amounts to standard, within-specification conditions.
                  The Heated bed specification says the bed can tolerate up to 115C, and some materials like ASA require 110C bed temp and the prints may be of long direction: this is after all an XL printer, able to accommodate large models, and they take a long time to print. Its completely unacceptable for the printer to complain of overtemp error, the components need to be higher rated !!!
                  If it needs a fan to achieve the specification, why then is that fan not already inbuilt, and why do I need to go out and adopt a 3RD party solution ?
                  The cost of the High temp version (STM32G071RBT3) of the MCU Board with 125C heat tolerance is $1.50 more than the sTM3232GO70R BT6 used on the board. And its a drop in replacement. Why not used ???
                  Reply

                  Topics

                  • Troubleshooting
                    • Printer troubleshooting
                      • 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)
                      • 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)
                      • 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 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)
                      • Nextruder filament sensor (CORE One, CORE One L, MK4/S, MK3.9/S, XL/+)
                      • 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)
                      • 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)
                      • 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)
                      • Chamber Mintemp error #31215 (CORE One) #35215 (CORE One L) #36215 (CORE One INDX)
                      • 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 L)
                      • Adjusting belt tension (CORE One/+, CORE One INDX, CORE One L/+)
                    • Diagnostics
                    • Print Quality Troubleshooting
                    • QR Error codes
                    • Print Error Messages