IBM 3746-900, Installation And Maintenance Manual

Page: 98 / 264

Display
If the panel is rolling, replace the display assembly. If that not correct the problem,
replace the video adapter (if installed) or replace the system board.
If the panel is not rolling, do the following to run the display self-test.
1. Power OFF the computer and display.
2. Disconnect the display signal cable.
3. Power ON the display.
4. Turn the brightness and contrast controls to their maximum setting.
5. Check for the following conditions:
The panel should be white or light gray, with a black margin (test margin)
on the panel.
You should be able to vary the panel intensity by adjusting the contrast and
brightness controls.
Note: The location of the test margin varies with the type of display. The
test margin might be on the top, bottom, or one or both sides.
If you do not see any test margin on the panel replace the display. If there is a
test margin on the panel, replace the video adapter (if installed) or replace the
system board.
Note: During the first two or three seconds after the display is powered on,
the following might occur while the display synchronizes with the
computer.
Unusual patterns or characters
Static, crackling, or clicking sounds
A “power-on hum” on larger displays
A noticeable odor might occur on new displays or displays recently
removed from storage.
These sounds, display patterns, and odors are normal; do not replace
any parts.
If you are unable to correct the problem, go to “Undetermined Problems” on
page 3-22.
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3745-XXA 3-18 3746-9X0: 6578 SPIM