Samsung TXN2771HFX/XAA Service Manual page 52

Troubleshooting
7-2 No Sound
Normal
Check
SPEAKER and WIRE
Abnormal
Check
TUNER B+ and SIF
7-2
NO SOUND
Check the
signal of CN601
Abnormal
Check the
input signal
of IC601
Normal
Check
IC601 B+
Normal
Check the signals
of pins 47,44,are input
Normal
Check the signals
of pins 25,24 are input
Normal
Repace IC601
Abnormal
Check the
input signal
of IC602 pins 7,11
Abnormal
CheckB+(BV) LINE
R815, IC805, FA802S
Normal
Check
IC602 B+
Normal
Replace IC602
Check FA803S
Samsung Electronics
Abnormal