Backlight Can't Be Turned On - Dell 1907FPf Service Manual

4. Backlight can't be turned on

No Raster
YES
LED Green
YES
Backlight cannot be
turned on.
YES
Is the voltage 12V at T1 PIN4?
Check U1 pin6 Voltage is 5V
YES
Check U1 pin1 Voltage is High
YES
Check T1/T2 pin8 and pin11 Open
Change T1/T2
or Short
NO
Check T850 or F850
NO
Check Q7 or Q6
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Service Manual