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 One L) #26205 (MK4S) #13205 (MK4) #27201 (MK3.9S) #21201 (MK3.9) #28201 (MK3.5S) #23201 (MK3.5)
The error happens when the printer's heatbed temperature goes above 125 ºC at any point. This is a safety feature to prevent printer damage. In this case, the printer will stop the heating and display the message on the screen.
How to fix it?
CORE One L
CORE One, MK4/S, MK3.9/S, MK3.5/S
Make sure that the ambient temperature where the printer is is stable, and above 10 ºC.
This error is usually caused by a damaged heatbed thermistor.
Check if the thermistor is well secured under the golden Kapton tape.
To test if the thermistor is damaged, go to the printer menu in Settings -> Temperature -> Heatbed temperature, and set it to 80 ºC. Then, move the heatbed cables by hand and see if the temperature will fluctuate. The thermistor must be replaced if the temperature fluctuates more than 5 ºC, from the set temperature.
Access your printer's xBuddy by opening the screws indicated below to access the heatbed cable connectors. Make sure that the heatbed power cable did not slip from the screw, and that the heatbed thermistor cable is well connected.
Open the xBuddyBox-cover and the el-box-cover by opening the screws indicated below to access the heatbed cable connectors. Make sure that the heatbed power cable did not slip from the screw, and that the heatbed thermistor cable is well connected.
If you have a multimeter, you can check the resistance of the cables using this guide: Multimeter usage
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| How to access the xBuddy board on the MK4/S and the CORE One | |
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