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 (CORE One L) #26206 (MK4S) #13206 (MK4) #27206 (MK3.9S) #21206 (MK3.9) #28206 (MK3.5S) #23206 (MK3.5)
This error is shown when the printer's nozzle temperature goes above 305 ºC at any point. This is a safety feature to prevent printer damage. The print will be stopped and the printer will cool down.
How to fix it?
This error is usually caused by the hotend thermistor.
Access the LoveBoard and check the heater and thermistor cables. Make sure that they are connected correctly and that there is no damage along their length.
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How to access the LoveBoard left side - CORE One
Using a T10 Torx key, loosen and remove one M3x6rT bolt. Then, release the side cover.
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How to access the LoveBoard left side - CORE One L
Using a 2.5mm Allen key, remove the M3x10 screw on top of the cover to release it.
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How to access the LoveBoard left side - MK4/S, MK3.9/S
Slide the LoveBoard cover upward to remove it from the Nextruder
On the xBuddy board, check if the fuse that protects the extruder is not damaged.
Make sure that the Loveboard main cable is correctly connected to the xBuddy board, and not pinched.
How to access the xBuddy board - CORE One
Locate the xBuddy board case. Looking at the printer from its rear, it is the rightmost case.
Using a T10 Torx key, remove six M3x4bT bolts to release the xBuddy box cover.
The bottom larger board is the xBuddy board, while the top smaller board is the xBuddy extension board.
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How to access the xBuddy board - CORE One L
Locate the Wi-Fi module on the rear panel of the printer. Using a 2.5 mm Allen key, remove the M3x14 screw. Gently pull the Wi-Fi module straight downward to remove it from the printer.
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From the inside of the printer, locate on the rear side the highlighted M3x4bT bolts.
Using a T10 Torx key, remove two M3x4rT bolts to release the rear xBuddy box cover. Lift the cover to expose the xBuddy and xBuddy extension boards.
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How to access the xBuddy board - MK4/S, MK3.9/S
Access the xBuddy board by loosening four M3x6 bolts.
Multimeter check
If you have a multimeter available, use this guide to check the resistance on the hotend heater and the hotend thermistor.
2 comments
I eventually replaced the love board and my problem was fixed. An electric static choc can indeed damage the loveboard.