Dell 1907FPf - No Picture & Backlight on

Service Manual
40
5. No picture & Backlight on
No picture & Backlight on
Touch OSD Menu Button,
Does OSD display?
Is there R.G.B signal
in
U401 #99, #96 #93?
Is there clock signal in
U401 #109?
Check DC
5.0
V on
CN501#1, #2, #3
Are there data
output on
U401#7~#16, #31~#40
Change U401
END
Change
D
301
,
D302 & D303
Check Q501 circuit
YES
YES
YES
YES
YES
NO
NO
NO
Change X401
NO