LG 42LC5DC (CHASSIS:LA65A) Service Manual ▷ View online
- 29 -
All Source Audio Trouble Shooting
Make sure you canít hear any audio
Check Signal
FB406, FB406, FB407, FB408
Check IC402 Power 3.3V, 2.6V, 1.2V
FB803, FB800, FB801
Replace FB
Y
N
Replace it
N
Check Connector
P400, P401
Y
Y
Replace connector
N
Check speaker
Y
Replace speaker
N
Maybe TPA3100D2 has problems.
Replace it
Y
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Digital TV Audio Trouble Shooting
Check video output
Follow procedure All source audio
trouble shooting
Y
Follow procedure digital TV video
trouble shooting
N
N
Maybe MSP4450K internal audio
DSP has problems. Replace it
Analog TV Audio Trouble Shooting
Check video output
Follow procedure All source audio
trouble shooting
Y
Follow procedure analog TV video
trouble shooting
N
N
Maybe MSP4450K audio block
has problems. Replace it
Check FB404 voltage level 19V
Replace it
N
Y
Check SIF signal
C400 / C846 / C847
Replace it
N
Y
Check SIF signal
R123
Replace it
N
Y
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Component / RGB / AV Audio Trouble Shooting
Check video output
Y
Follow procedure
external input video
trouble shooting
N
Check Connector
J500 (Component)
J503 (RGB)
J501 / P500 & cable
(AV Rear, AV Side)
Replace connector
N
Y
Check signal
C1510 / R1585 / C1511 / R1586
(Component)
C1515 / R1587 / C1516 / R1588
(RGB)
C1512 / R1589 / C1513 / R1590
(AV Rear)
FB514 / FB515
(AV Side)
Replace it
N
Y
Check IC402 power FB404 voltage
level 19V
Replace it
N
Y
Maybe TPA3100D2 has problems
HDMI Audio Trouble Shooting
Check video output
Follow procedure All source audio
trouble shooting
Y
Follow procedure HDMI video
trouble shooting
N
N
Maybe MSP4450K audio block
has problems. Replace it
Check EDID NVRAM (IC301)
Power & I2C Signal (#5, #6)
Replace it or redownload
Y
N
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BLOCK DIAGRAM
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