LG 22LU7000 - Page 25

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5. In case of no sound
(1) Symptom
1) LED is blue.
2) Screen display but sound is not output
(2) In case of no sound to speaker
All input mode
is no sound?
Yes
Is VCC “+12V”
(JP1:1pin) and L5 normal?
No
No
Replace Power
Boar
d& U2(FET)
Yes
Is the speaker
on it Audio
menu?
No
Check the
Speaker Cable
Only HDMI is
no sound?
Download
the EDID data.
No
Only TV is
no sound?
No
Yes
Check the Tuner
In/Out
Yes
Only AV/PC input is no
sound?
No
Check the in
p
ut source.
Yes
Re
p
lace Main Board.
Set on speaker
in Audio menu
Is the Speaker
Cable normal?
Yes
No
Only Componet/ DVD
input is no sound?
Is the output of U741
normal?
No
Yes
Yes
U112 operate
normal?
Replace U112
(FLI10610H)
U761 operate
normal?
Replace U761
(NTP
-
3000A)
No
No
Yes
Yes
Re
p
lace Main Board.
No
Replace U714
(CD4052)
Check the input source &DVD
player.
Yes
Block B