LG 55LM4610 / 55LM4650 (CHASSIS:LB21B) Service Manual ▷ View online
- 21 -
8. All Source Audio
Check the TV Speaker Menu
(Menu -> Sound -> TV Speaker)
On
ok
ok
Check Output Signal P501
1, 2, 3, 4 pin.
Replace Audio AMP IC(IC501)
ok
No
Check Connector & P501
Replace connector
if found to be damaged.
ok
No
Check speaker resistance
and connector damage.
Replace speaker.
ok
No
Off
Toggle the Menu
Check AMP IC(IC501) Power
24V, 3.3V
No
Replace Amp IC(IC501)
Check Mstar I2S Output
IC501 9,10,11 Pin
No
Check signal line. Or replace Mstar(IC101)
Check Mstar AUDIO_MASTER_CLK
R148
No
Replace Mstar(IC101) or Main Board
.
ok
Check AMP I2C Line
R140, R141
No
Check signal line. Or replace Mstar(IC101)
- 22 -
9. Digital TV Audio
Check RF Cable & Signal
Follow procedure
‘8. All source audio’
trouble shooting guide.
ok
Check Tuner 3.3V Power
L3703
Replace L3703
Check Tuner 1.8V Power
IC3703 2 pin : 1.8V
Check IF_P/N Signal
TU3700 10/11 Pin
Replace IC3703
ok
ok
ok
No
No
No
Bad Tuner. Replace Tuner
.
Check RF Cable & Signal
Follow procedure
‘8. All source audio’
trouble shooting guide.
ok
Check Tuner 3.3V Power
L3703
Replace L3703
Check Tuner 1.8V Power
IC3703 2 pin : 1.8V
Check SIF Signal
TU3700 6 Pin
Replace IC3703 .
ok
ok
ok
No
No
No
Bad Tuner. Replace Tuner
.
10. Analog TV Audio
- 23 -
11. AV Audio
Check AV Cable for damage
for damage or open conductor
Check JK1601 & Signal Line
R1632, R1633
ok
ok
No
Replace Jack
Follow procedure
‘8. All source audio’
trouble shooting guide.
12. Component Audio
Check Component Cable
for damage or open conductor.
Check JK1601 & Signal Line
R1632, R1633, R1617, R1618
ok
ok
No
Replace Jack
Follow procedure
‘8. All source audio’
trouble shooting guide.
13. RGB Audio
Check Cable conductors
for damage or open conductor
Check JK1102 & Signal Line
R1107, R1108
ok
No
ok
Replace Jack
Follow procedure
‘8. All source audio’
trouble shooting guide.
- 24 -
R
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(J
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Main SO
C
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(L
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(IC
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A
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(J
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HDMI1 (J
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3)
C
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H
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D
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:
AP
21
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(IC
14
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+5
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1
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(O
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(J
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(1Gbit
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Serial Flas
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IC
14
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IC
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R
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R
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R
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C
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RXB0+/-~RXB4
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Sy
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EP
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BLOCK DIAGRAM
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