Compaq 400 486 DX2/40 MHZ 250 MB 4 MB 9.5 Personal Computer User Manual


 
"jailbars" pattern), a. System board
has a single color b. Display panel
on it, or has garbled c. Inverter board
graphics across the ---------------------------------------------------
entire panel. This Defective display Replace the display cable.
failure is for cable
patterns across the ---------------------------------------------------
entire panel (not Defective inverter Replace the inverter board.
just on one section). board.
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Defective system Replace the system board.
board.
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A single line, small Defective display Replace the display panel.
group of lines, or panel
block appears on the
display panel. This
failure occurs in
only a section of the
display panel. ****
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A number of single Acceptable according Check the number of pixels
pixels are out or to specifications. that are out against Compaq
dots of various specifications. A certain
colors are visible number of pixels are
on a black screen. allowed to be out, due to
limitations in LCD
technology.
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Defective display If the number of pixels
panel. that are out is beyond
Compaq specifications,
replace the display panel.
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Defective system Replace system board.
board.
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* Press the Fn + F9 keys to adjust the brightness, setting.
Additionally, on the MSTN and CSTN models, press the Fn + F8 keys to
adjust the contrast setting.
** When using an external monitor and simultaneously displaying an image
on the internal display, the image on the external monitor may not
fill the screen.
*** This problem indicates that the backlight or its power circuitry has
failed. Since you cannot observe the POST results on the display panel
when the backlight is not functioning, connect the unit to an external
monitor before powering the unit up. If an external monitor is not
available, verify that POST completes by listening for the single or
double beep, and watching for the indicators to turn on at the top of
the keyboard.
**** Blocks usually appear in an even fraction of the display (1/2, 1/4,
1/6, 1/8, etc.).
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Table 5-18. Solving Diskette/Diskette Drive Problems
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Problem Probable Cause Solution(s)