Ultrospec 6300 pro display back light off

I just pulled an old Amersham GE Ultospec 6300pro down from a shelf and it boots right up and passes calibration. However, the display's backlight is not on. Is there an option to turn it on, or has it failed? I looked everywhere (lab and online) for an operator manual, but no luck. I found an option to change contrast to the display, but not much help. There is a Service section, but requires pass word. This is a nice unit, but hard to see the screen without the backlight.... Thanks all!!