User`s guide

Troubleshooting First Checklist/ - 3
A maladjusted screen can mimic the
symptoms of main deflection board or CRT
failures.
By performing the adjustment procedures, you might determine if
one or more of the adjustments is the cause of the problem.
Variances in screen color and brightness are
usually caused by the setup controls or the
environment.
Screen color purity over the entire screen is never perfect. CRT
tolerances allow for some distortion.
Try adjusting the rotation, brightness, or contrast to reduce or
eliminate the symptom.
Color imperfections can be caused by magnetized metal objects
(desks, file cabinets, etc.). Move the unit to a different location if
you notice color blotches or a change in brightness on an area of
the screen. If the display changes (for better or worse) when you
move it to another location, the environment is the source of the
problem. Relocate the monitor or move the distortion-causing
object.
If you suspect a failure, check the monitor
serial number before replacing modules
• If the monitor serial number is between SG522xxxxxx and
SG536xxxxxx, contact Apple Technical Support (1-800-
919-2775, option 6) to expedite replacement of the head unit
or whole unit.
• If the number is SG537xxxxxx or greater, refer to the
Symptom Charts to troubleshoot the monitor.