I recently installed a new PCB (Creality V2.2) as the Cura software could not see my printer and have had a problem with the USB socket before.. However, I replaced the PCB and it still will not see the printer. I decided to load a file onto a SD card and print from that. I tried to level to bed and it does the first level OK but when I press next the bed just keeps going forward until it hits the end and then after a split second the Stepper motor stops. This occurs on the next 3 levelling areas. How can I stop this? Is there any form of adjustment that I can make via the control unit or is the PCB faulty? looking forward to seeing your replies.