So far we have a few similar cases reported. We suspect, during winter time, the static charge accumulated on the extruder fried the extruder stepper driver.One way we believe to prevent this is to remove the paint around the screw hole that holding the extruder to rail slider, see the following picture:
This will allow better conductivity between extruder and print body. We did this emergency fix for most of the printers shipped.Please check if your extruder is like this or not.
Any way we will send you a replacement mainboard, send an email to support@cetus3d.com.
The replacement part will be send ASAP.
Regards,
Jason Wu
Cetus Team