LG 29FS2AMB/ANX Service Manual page 19

5. No raster
Is the voltage at VCC of IC001
ST_1.8V and ST_3.3V?
NO
Check/
Replace IC500
NO
Check/ Replace
Q422, T402
OK
YES
Does the square
waveform from PIN
23 of IC500 appear
YES
Is the waveform at
Drain Q408 normal?
Check +B voltage
125 ~ 135V or
NO
Check ST_Voltage
YES
Check IIC bus
lime (SDA, SAC)
- 19 -
0V
Check F1701 Fuse
on PSW Board
OK Check/ Replace F1771
Check the voltage of
C1806
Check/ Replace D1810
Check the voltage at
pin2 of IC801
Check/ Replace IC810
Check the voltage at
P803B 5.6V
Check the output
IC830, IC840, IC843
OPEN
0V
0V