LCD Control panel knob non operable

[Rufusruffkutt]

I have just completed building my printer , having checked and checked again, it was ready run, the LCD Panel say's "ready"
I have downloaded easy print , and can communicate between between my PC and printer via USB, I have connected to printer via software, and still the printer is idle, The control panel knob, on the LCD Screen on printer, when turned has no effect , except the FR% Value change's.
I have double and triple checked my wiring and I am correct to Schematic wiring drawing, i suspect the GT2560 Board is faulty ,Any advice wold be helpful