Are you talking about the workstation?
Tap the top of the screens in this order: LEFT, RIGHT, LEFT.
It will then give you a6 digit number. Ex: 189255
Multiply the first two digits (1x8), then add the 4th and 6th numbers to the sum of the first two.
Ex: 189255, 1*8+2+5 = 15.
It will then take you to the diagnostic screen. Select the Go to Windows.