Welcome to the SeeMeCNC Community

I experienced some problems with my Rostock V2 when I blew a fuse. I replaced it and I had problems with the hotend getting plugged, then the extruder stopped working. I ordered a new extruder motor and it still does not work. I note my board has a yellow set of LED flashing
Marked T and X
The 3 stepper motors on the X Y and Z axis are working as are the fans.

Any help??
Thnx
Dennis

Just out of curiosity, what is your hotend temp when you try to extrude? If it's too low then the extruder won't run.

The next thing to try is to unplug one of your axis steppers (X, Y, or Z) and plug your extruder stepper into it. Now does it run when you do a move?