XOCECO PH42T7, Service Manual

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23
Trouble shooting guide
1.No raster, no picture, no sound
NOTICE: The PDP power supply have the protection function of overcurrent, overvoltage
and so on, if certain route power supply appear overcurrent and overvoltage, the power
supply should appear the protection to arise no-output.
Check if the power supply indicator light is on.
Check 5V-STBY
Cut off the connection
between power supply
board and data board, and
test 5V-STBY
Check N401
and keyboard.
The problem of
power supplies
board.
Check power supply
D3.3V, D5V
Measure the level of 8
th
pin of X405:
when use V4 screen, it should be low
level; when use V7 screen, it should
be high level.
Check the level
of power supply
pin of each IC.
Check if the
union joint of
N602 and LVDS
line is loose.
Check N401
No raster, no picture, no sound.
yes
Normal
no
Abnormal
Normal
Abnormal
Abnormal Normal