Samsung PLK405WX/XAC Service Manual page 47

Troubleshooting
6-16 No Sound
6-12
Internal speaker selected?
Yes
Volume ok?
Yes
Check Main-L, Main-R
signal output from AV
Switch Board
Yes
Check L,G signal
supply to IC601 (Sound AMP)
Yes
Check +34V (IC601 pin3)
Yes
Check IC601 pin5:LOW(0)
Yes
Check the sound
output from IC601 pin 7,11
Yes
Check REL601
Yes
Check
speaker connections
No
Select the internal
speaker
No
Adjust the Volume
No
Check AV
Switch Board
Chek C616, C617,
No
R614, R615, C601, C602,
C603, C604, R604, R601
No
See No +34V of AP2
No
Check Q601, Q602
(IC901 pin54:LOW)
No
Check IC601
No
Check REL601
Samsung Electronics