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: #31309 (CORE One) #26309 (MK4S) #13309 (MK4) #27309 (MK3.9S) #21309 (MK3.9) #28309 (MK3.5S) #23309 (MK3.5) #12309 (MINI)
The error is shown when there is a damaged cable on the heatbed or any of its connections.
How to fix it?
Avoid touching the surface of the xBuddy/Buddy mainboard, touch it only from its edges.
The most likely cause of this issue is damage to the heatbed cable. Check the path between the heatbed and the xBuddy/Buddy board, and see if there are any parts that are broken or pinched.
In case there is no damage, check the cable connection to the heatbed and to the xBuddy/Buddy board. Try reconnecting the connectors.
In rare cases, this error message can be shown in case of damage to the mainboard. So if the cables and connectors are intact, try checking the board for any damage.
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| CORE One heatbed | MK4/S, MK3.9/S, MK3.5/S heatbed |
xBuddy board (CORE One, MK4/S, MK3.9/S, MK3.5/S)
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| MINI/+ heatbed (bottom) | MINI/+ heatbed (top) |
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| MINI/+ Buddy board | MINI/+ Buddy board |
17 comments
When starting with the MK4 cold, selecting a file to print, and then starting the print, all the steppers and the bed heater and the hot end are turned on all at once, causing a current surge large enough to trigger the over-current sensor. So pre-heating reduces that surge when the other things are powered up at the start of a print, and printing can then be initiated. I would suggest that the firmware needs to be revised to apply power to the steppers, bed heater and hot end sequentially.