LG 42LH50 (CHASSIS:LA91L) Service Manual ▷ View online
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8. All Source Audio
Make sure you
can’t hear any audio.
can’t hear any audio.
First check the TV
SPEAKER Menu
SPEAKER Menu
Toggle the menu
NO
OK
Check Connector &
P2300
P2300
Replace connector
if found to be damaged.
if found to be damaged.
NO
Check speaker resistance
and connector damage.
and connector damage.
Replace speaker.
NO
OK
Check AUDIO_M_CLK
R2302
R2302
Replace BCM3549
(IC100) or Main board
(IC100) or Main board
NO
OK
Check Mstar I2S Output
R2304, R2305, R2306
R2304, R2305, R2306
Check signal line
Or replace IC100
Or replace IC100
NO
OK
Check IC2301 Power
*24V, 3.3V, 1.8V.
*24V, 3.3V, 1.8V.
Check Regulaor
IC2300.IC2404
IC2300.IC2404
NO
OK
Check Output Signal
P2300 1,2,3,4 PIN
P2300 1,2,3,4 PIN
Replace NTP(Audio AMP)
IC2301
IC2301
NO
OK
OK
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9. Digital TV Audio
Check Tuner 5V Power
TU2500 4Pin
TU2500 4Pin
Check IC2502
NO
Check Connector &
P2300
P2300
Replace connector
if found to be damaged.
if found to be damaged.
NO
Check speaker resistance
and connector damage.
and connector damage.
Replace speaker.
NO
OK
Check IF_P/N Signal
Replace Tuner.
NO
OK
Check Check
Demodulator Input
Clock(X1100-12MHz)
Demodulator Input
Clock(X1100-12MHz)
Replace X1100
NO
OK
Check IC1101Output
Replace IC1101
NO
OK
Check Output Signal
P2300 1,2,3,4 PIN
P2300 1,2,3,4 PIN
Replace NTP(Audio AMP)
IC2301
IC2301
NO
OK
OK
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10. Analog TV Audio
Check RF Cable
OK
Check Tuner 5V Power
TU2500 4Pin
TU2500 4Pin
Check IC2502
NO
Bad Tuner. Replace
Tuner.
Tuner.
NO
OK
Check SIF buffer signal.
Check SIF Signal line.
NO
OK
Follow procedure All
source audio
source audio
Replace BCM3549
(IC100) or Main board
(IC100) or Main board
NO
11. USB
Check Lamp blinking
Check USB 5V Power
(JK3401 1pin 5V Check)
(JK3401 1pin 5V Check)
NO
Check IC3400 1,6 pin
5V power
5V power
NO
Replace the IC3400
NO
OK
Check the supporting
format
format
Change to the supporting
format
format
NO
12. Networking problems (Netfix/Yahoo!)
Check ethernet.
(Is the internet supported?)
(Is the internet supported?)
OK
Check LAN Cable.
OK
Check JK3400
(Check Lamp blinking)
(Check Lamp blinking)
Check pin 2,5
(2.5V Power)
(2.5V Power)
NO
OK
Check IP Setting
Resetting IP
(Auto or Manual)
(Auto or Manual)
NO
OK
Function Execution
(Yahoo!/Netfix)
(Yahoo!/Netfix)
Ask to Yahoo!/Netfix CS.
NO
Replace Jack.
NO
• 400MHz MIPS CPU
• Full HD 1080p60
• Dual HDMI 1080p60 inputs
• Integrated dual link LVDS Tx
• 10-bit video processing
• AVC/MPEG-2/VC-1 video decoder
• Advanced Audio Processor
• Integrated ATSC/QAM demodulators
• Integrated IF demodulator
• Dual USB 2.0
• Ethernet (MAC/PHY)
• Advanced 3D graphics
• Full HD 1080p60
• Dual HDMI 1080p60 inputs
• Integrated dual link LVDS Tx
• 10-bit video processing
• AVC/MPEG-2/VC-1 video decoder
• Advanced Audio Processor
• Integrated ATSC/QAM demodulators
• Integrated IF demodulator
• Dual USB 2.0
• Ethernet (MAC/PHY)
• Advanced 3D graphics
BCM3549
RF
SIF
CVBS
Tuner
TDVW-H103F
IF
HDMI 4:1
Switch
(TDA9996HL)
5 Analog L/R
Rear CVBS
EDID
M24C02
R/G/B
2 YPbPr
DDC
TMDS
TMDS/DDC
UART
RS-232C
(MAX3232)
MiCom
(MTV416)
2KB
EEPROM
Reset IC
(KIA7029)
RESET
Reset IC
(KIA7029)
I2C
To IR Board
Audio AMP
(NTP3100L)
+5V_USB
OVER
CURRENT
USB Power
(MIC2009)
USB2.0
I2S
L
R
SPDIF
256MB
NAND Flash
Memory
256MB
DDR2-1066
SDRAM 128MBx2
64KB
EEPROM
DDR2 I/F
32bits
NAND I/F
I2C
Ethernet
Antenna In
& Cable In
2 Composite
2 Component &
1 RGB In
4 HDMI In
Debug Port
To 120Hz
LCD Module
LCD Module
Ethernet Jack
SPDIF Out
Speaker Out
USB 2.0
Side CVBS
Inverter
74HC14D
H/V Sync
Level Sh.
SSM6N15
FRC
(MST7329N)
FRC DDR2
64MB(32MBx2)
FRC Serial
Flash 256KB
LVDS
I2C
LVDS
CEC
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