Hello,
The Situation:
last week I printed a relativly big Model on the UM3, using a Polycarbonate Filament. The print lost the adhesion to the buildplate over night. As I came back to the Printer the next day, the PC embraced the Printcore and parts of the printhead. After I managed to rescue the Head and the core I reassembled everything and connected the Head wit the rest of printer and switched it on.
After approximately a minute the Error 18 was Displayed.
Summarized, the Error says no or no proper communication between Printer and Printhead.
Since then, at every boot the Ultimaker lo