Hi - New to cnc, Everything was working well yesterday.
This morning - unit would not come to home and z axis will not move up and down, others are fine - spindle is rotating. However, the top belt is not moving and can not be moved manually. I can hear it trying to move - it’s like it’s stuck in the top position. Maybe went too far and is now stuck.
When you first start the homing the Z axis is the first thing that should raise up, then the X and Y.
Is the Z axis all the way at the top? If so turn off the power and manually lower the Z axis, then turn it back on and see if the Z axis raises and touched the homing switch. If no power is going to the stepper motor you should be able to move it manually. Unless a wire came loose somewhere
Try what rustle said, also another possibility if the sound is not a grinding sound, Is that the set screws holding the pulley to the stepper shaft could be loose and the stepper rotating in the pulley…