HP LE1851w Service Manual page 35

18.5" LCD Color Monitor
2. W/LED No Backlight
Check ON/OFF signal
Check IC801 pin2=5V ?
Check the pin1 of IC801 have saw tooth wave
Check Q802 has the output of square wave at short time.
Check the resonant wave of pin2 & pin5 for T801
Check the output of T801
Check connecter & lamp
Check Q805 =12V
NG
OK
NG
OK
OK
NG
OK
NG
OK
NG
OK
NG
OK
Check Q805
Check Interface board
NG
Change D817,R827
Change IC801
CheckC802/C824/R839/R850
Check C839/R855/R856/C838
Change T801
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HP LE1851w