NEC DSC-3261HA Service Manual page 18

Trouble Shooting Charts
5. NO SOUND(PICTURE OK)
Check
direction & connection
of
H/P Connector(P503) &
AV3 Connector(P504)
Check
6th pin of I701
(normal:Low)
Check signal at
28, 29, 58th pin of I601
NORMAL
Check
20V line of I602:OK
Lin, Rin: OK
Lout, Rout: NG
NORMAL
Check
20V line of I602:OK
Lin, Rin: OK
Lout, Rout: OK
Check/Replace
Speaker
ABNORMAL
ABNORMAL
Check/Replace
SF03, I101
ABNORMAL
17
Check
12th pin of I101
NORMAL
Check/Replace
X601 &
SCL, SDA line of I601
Replace
I602