Dell E178FPC Service Manual page 49

17" LCD Color Monitor
No Backlight
Check CN902 Pin 3, 4=12V
OK
Check ON/OFF signal
OK
Check IC801 PIN2=5V
OK
Check IC801 PIN13 have triangle wave
OK
Check IC801 PIN1/PIN15 PWM wave
OK
Check the output of PT801, PT802
OK
Check connecter & lamp
NG
Check adapter and F902
NG
Check Interface board or main board
NG
Change on/off circuit
NG
Change IC801, C807-C810
NG
Check Q805/Q806
NG
Change PT801, PT802
49
Dell E178FPC