When I auto home the X and Y axis move fine and do what they have to do.
The Z axis however sometimes just turns the wrong way and the bed goes down instead of up.
Also in moving the axis via the menu the motor irradicly moves by going up and down really fast when I move the wheel.
What have I already done?
re-installed firmware.
swapped motors.
swapped drivers ( voltage check om all were good to)
Check the end stop for the Z axis make sure the cables are seated on the end stop and the board.
Make sure the end stop is clean.
When you updated the firmware did you use Arduino software 1.0.6 or below?
If not you can find it in this link. https://www.arduino.cc/en/Main/OldSoftwareReleases#previous