Z AXIS clanking after getting new CPU

Hi guys,
I have the cetus3d MK2 standard and I replaced the CPU with a brand new one because mine stopped working. After a succesful install, when I initialize the machine, the Z goes up and and up and up and never stops - until it CLANKS - until I stop the machine. Cetus support is unable to help. I wonder if they sent me a CPU for an extended model. I had bought 3 spare CPUs and they all do the same behavior. Z axis does not stop and clanks.

Any ideas?

Thank you

Flash the correct firmware. The mk1 and mk3 have hardswitches installed. The mk2 does not have these. After you assured that the correct firmware for your model is installed do the axis endpoint calibration described in your manual.