Stepper motor on extruder may be fried after firmware update...
I was having trouble with a print that kept failing, so I finally updated to the latest firmware on my mini+ . The print worked perfectly. Ran a few more smaller prints after. I started one more small print before heading down to grab some dinner. On checking the printer a while later, I saw the print had stopped after the first few millimeters. I thought maybe the nozzle was clogged, so I told the printer to purge. When the stepper motor on the extruder fired up, it just started making a weird hissing noise and nothing turned. I even took the entire extruder assembly apart and tried to tell it to advance the motor a few steps. It just started making that hissing noise again. Has anyone else experienced something similar to this?
RE: Stepper motor on extruder may be fried after firmware update...
Try to rotate it with fingers when the printer is off and check if you can feel any noticeable obstructions.
If there are none and it still does not move after power on then try to rearrange the cables from the board to the extruder ( sometimes interferences happen), try factory reset. If that does not help then you probably need a new motor or motherboard ( this also can fry due to excessive load).
See my GitHub and printables.com for some 3d stuff that you may like.