LG CF-21Q20EH Service Manual page 14

No Sound(Picture OK)
pin10 of IC601(Sound Amp)
0V
Check & Replace
F851,FB853,D850
Yes
Check the voltage
at pin8 of IC601
0V
Check & Replace
IC601,QN01-02,P605(6)A
No Sound from H/P Jack(Option)
(Main Sound OK)
Check the waveform
at pin21,22 of ICN01
No
Check & Replace
ICN01
Check the voltage at
Check the waveform
at pin24,25 of ICN01
Check the waveform
at pin47 of ICN01
5V
Check & Replace
Q601,IC01
NORMAL
Check & Replace
XN01,ICN01
NORMAL
Check & Replace
IC01
Normal
Check the waveform
at pin1,3 of ICN02
Normal
Check & Replace
P605(6)A,H/P Jack
- 14 -
32V
No
No
Check the waveform
at pin12 of IC141
Check & Replace
Z102,IC141
Abnormal
Check & Replace
ICN02
No