Dell S1909WNf Service Manual page 34

5. Backlight on, key function and LED accurate indication ok but no picture
Backlight on, key function and LED
accurate indication ok but no picture
IS the display is white and cannot
display OSD when press key?
Is display selftest picture at
VGA mode?
Is there DVI signal in U104
#39, #40, #42, #4, #45, #46,
#48 #49?
Change
D108,D109,D110,D111,D112,
D113,D114,D115
YES
YES
NO
VGA
DVI(NA)
YES
DVI(NA)
Check DC 5.0V on
CN101#1, #2
Is there R.G.B signal in
U105#28, #25 #23?
Yes
Are there data output on
U105#91~#100,
#77~#86
No
Change U105
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Service Manual
NO
Is the panel enable
signal at #73 of
U105,if no check
Q104 circuit or change
U105,if yes Check
Q101 circuit
NO
Change D103,
D104 & D105
YES
Is the FFC cable
inserting ok,if no
reinsert else
change FFC cable