In desperate need of help with new Prusa

[brucehvn]

There is usually a setting in the firmware to prevent cold extrudes. This will keep the extruder motor from running unless the hotend temperature is above a certain threshold. It's not clear what firmware you are running, but in the Marlin Configuration.h, it looks like this:

//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
//can be software-disabled for whatever purposes by
#define PREVENT_DANGEROUS_EXTRUDE
//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
#define PREVENT_LENGTHY_EXTRUDE

#define EXTRUDE_MINTEMP 170

In this case, the firmware will not allow the extruder motor to run unless the hotend is above 170 degrees.

Bruce