Samsung HCH551WX Service Manual page 26

4-5 No Sound (Picture OK)
Samsung Electronics
Check the voltage
of IC665 pin3 (34V)
Normal
Check the voltage
of IC665 pin9 (15V)
Normal
Check the audio
signal of CN601 pins 1,3,5
Normal
Check the circuitry near
of QN21,QN22,QN23
Normal
Check the circuitry near
of ICN05, ICN06, ICN07
Normal
Check
the circuitry near of
IC603,604,605,606,607
Normal
Check the Digital Board
Abnormal
Check Power
Supply Line (34V)
Abnormal
Check IC665,IC666
Abnormal
Check Q665,Q666,Q667
and Mute Circuits
Abnormal
Replace QN21,
QN22,QN23
Abnormal
Replace ICN05,
ICN06, ICN07
Abnormal
Replace IC603,
604,605,606,607
Troubleshooting
4-3