Im getting a message telling me that I have a error code key 74 ,as I my endstop for the stepper Z , must be between min and max !! and the printer wont work as it cannot be detected ! Anybody know what to do here ? I hope so 
Can you please post a pic of the error screen…??
I’ve never heard of this code, is this Klipper…??
Sorry, I don’t know anything about Klipper…
Did you follow what the readout says about the guidelines & configuration files.
Did you contact Creality…??
Someone else here might be able to help.
It all worked well untill yeterday ! Ive been printing with it for over a year now and a few problems ,it all started yesterday with the print layers looking very bad,I put a new nozzle on just incase then all this started ! The more complicated things you use on printers the deeper shit you get in !!
Someone has just given me a good idea , when I changed the nozzle I could have damaged the Z sensor !
Unless you are a brute it is complicated to damage the z sensor by changing the nozzle.
If you changed the nozzle then the Z-Offset would change, but in Klipper I don’t know if it would set it automatically or if you would still have to manually set it.