LG Flatron W1943SB - Troubleshooting - Raster;Lamp Issues

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6. RASTER
Unplug backlight connector wire,
check PT801 pin7/pin8 = 650V?
Replace PT801
NO
NO
YES
Check PT801
pin7/pin8= 650V?
Replace Q806
Check C807, C809,
C810
Replace backlight
YES
Replace IC801
NO
Check Q806 pin5,
pin6 is 14.5V?
Cut all the pin connector of Q806,
check C811 (+) =14.5V?
CheckIC801 pin
2=5V?
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Check C807, C809, C810
Check IC801 pin 5/pin6
NO Raster
(Lamp Off)
Check C811 (+)
=
1
4.5
V
Check ON/OFF
signal
Check power section
Check Interface section or
main board
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NO
NO
NO
YES
YES
Check IC801
Pin1/pin15 have the
output of sawtooth
YES
NO
YES
NO
YES
NO
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