@garr86 check if the Z axis end-switch is working properly. If you have a spare one just plug the socket to the spare one and press auto home on printer, it should move downwards and at some point you need to press the spare end-switch and see if it works. You can understand it by observing the Z axis movement, it should stop when you press the end-switch.
If ıt stops then detach the mounted end-switch on printer and replace it with the spare one. It solved my problem with printer.