Envision EN9110, Service Manual

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III There is interferences in DOS mode
NOTE: the criteria of doing AUTO-CONFIGURATION: must be a full-size screen, if the
screen not full, the auto-configuration will fail. So in DOS mode, just set your “CLOCK” in
OSD-MENU to zero or use some EDITOR software which can full fill the whole screen (ex:
PE2, HE) and then press “AUTO” Or you can use “DOS1.EXE” which attached in your
Driver disk to optimize DOS mode performance.
IV The panel luminance is down
Use white pattern and resolution 1280x1024 @ 60Hz, CHROMA 7120 measured the
center of panel
6-2-2 INVERTER –MODULE TROUBLE SHOOTING CHART
*
*Note: the Waveform of U901 pin 2 can determined the power situation
1. Stable rectangle waveform with equal duty, freq around 150K-158KHz
that means all power of this interface board is in normal operation
, And all status of 5V & 3.3V is working well
2. Unstable or uneven rectangle waveform without same duty, that means
ABNORMAL operation was happened, check 3.3V or 5V, if short-circuit or bad
component
3. Rectangle waveform with large spike & harmonic pulse on front side means all
3.3v is no load, U600
Gm5020
was shut-down, and only U502
MCU
still working,
that means the monitor is in power saving status, all power system is working
well.
Set Contrast, brightness =maximal, RGB= 50
Quit from OSD-screen, measured Y (luminance)
With chroma 7120, check Y= 230
±
10 cd/m2?
NG
If the Y less than 200 cd/m2 (after the contrast,
brightness = max) then change the LAMP of panel
If Y can reach
＞
240 cd/m2 that means
The lamp still working well, so we just re-do the
white-balance process
As following procedure
OK
Use white-pattern, press MENU button along
with AC power-plug in (you will in factory
mode) The OSD-menu will be at left top of
screen,
Press AUTO button to automatically adjust black
level value, you will see the sign PASS
Follow White-Balance, Luminance adjustment
as above, method to more detail procedure
For do a white-balance adjust
OK