DOWNLOAD LG 42LH70YD (CHASSIS:LJ91D) Service Manual ↓ Size: 10.45 MB | Pages: 73 in PDF or view online for FREE

Model
42LH70YD (CHASSIS:LJ91D)
Pages
73
Size
10.45 MB
Type
PDF
Document
Service Manual
Brand
Device
TV / LCD
File
42lh70yd-chassis-lj91d.pdf
Date

LG 42LH70YD (CHASSIS:LJ91D) Service Manual ▷ View online

9. All Source Audio Trouble Shooting
D-sub RGB
HDMI 1
AV2
SIDE_CVBS, SIDE_L/R, SIDE_DET
DDR2 (1Gbit)
Elpida/Hynix
NAND Flash
(512Mbit)
Digital Audio (Optic)
USB
Digital AMP
NTP3100L
RS-232C (Ctrl./SVC)
3x1 
HDMI Switch
I2S
NVRAM
RGB/H/V
VA1G5BF8005
DDR_Data[0:15], DQS, DM …
DDR2 (1Gbit)
Elpida/Hynix
Data[16:31]
Addr.[0:13], ctrl. data
MICOM
(MTV416GMF)
MAX3232
BCM3556
BCM3556
(Brazil)
(Brazil)
Data [0 … 7]
TU_SCLK, TU_SDATA, TU_SYNC
TU_SIF
TU_CVBS_IN
X-tal
RF_Switch, Gain_Switch
SDA0/SCL0_3.3V 
Reset Switch
JTAG
CLK,TDI,TDO,MS,RST
X-tal
24MHz
AV1
Component 1
Y Pb Pr, L/R, DET
CVBS, L/R, AV_DET
CS ,RE,WE……
Component 2
Y Pb Pr, L/R, DET
Audio L/R
Audio L/R (for RGB)
HDMI 2
HDMI 3
SPDIF
RX/TX
RX/TX
Reset IC
54MHz
JACK BACK
JACK BACK
at REAR
at REAR
SCL, SDA_3.3V
SCL, SDA_3.3V
FRC IC
(MST7323S)
DDR2(256Mbit)
Qimonda/Hynix
FRC Block
FRC Block
LVDS
LCD Module
(FHD, 120Hz)
Overall Block Diagram
for Brazil DTV (LH70)
X-tal
12MHz
Bluetooth Module
DP1/DM1
USB_DM1
USB_DP1
DP2/DM2 
USB_DM2
USB_DP2
O.C. Protector
+5V
+5V
9. All Source Audio Trouble Shooting
Make sure you can’t hear any audio
Y
Check Connector P501
N
Y
Y
Check Speaker
Replace Connector
Check Signal
L504, L505
N
Replace one of 
L508/L509/L510/L507/L504/L505
& Recheck
Y
Check IC501 Power
24V, 3.3V, 1.8V
L511, L503, L501
N
Replace one of 
L511L503/L501 and IC503
& Recheck
Y
Check BCM3556 I2S Output
R505, R506, R507
N
Replace It & Recheck
Y
Maybe BCM3556(IC100)
has problems
Replace Speaker
N
N
Maybe NTP3100 has problems.
Replace It
N
N
N
10. Digital TV Audio Trouble Shooting
D-sub RGB
HDMI 1
AV2
SIDE_CVBS, SIDE_L/R, SIDE_DET
DDR2 (1Gbit)
Elpida/Hynix
NAND Flash
(512Mbit)
Digital Audio (Optic)
USB
Digital AMP
NTP3100L
RS-232C (Ctrl./SVC)
3x1 
HDMI Switch
I2S
NVRAM
RGB/H/V
VA1G5BF8005
DDR_Data[0:15], DQS, DM …
DDR2 (1Gbit)
Elpida/Hynix
Data[16:31]
Addr.[0:13], ctrl. data
MICOM
(MTV416GMF)
MAX3232
BCM3556
BCM3556
(Brazil)
(Brazil)
Data [0 … 7]
TU_SCLK, TU_SDATA, TU_SYNC
TU_SIF
TU_CVBS_IN
X-tal
RF_Switch, Gain_Switch
SDA0/SCL0_3.3V 
Reset Switch
JTAG
CLK,TDI,TDO,MS,RST
X-tal
24MHz
AV1
Component 1
Y Pb Pr, L/R, DET
CVBS, L/R, AV_DET
CS ,RE,WE……
Component 2
Y Pb Pr, L/R, DET
Audio L/R
Audio L/R (for RGB)
HDMI 2
HDMI 3
SPDIF
RX/TX
RX/TX
Reset IC
54MHz
JACK BACK
JACK BACK
at REAR
at REAR
SCL, SDA_3.3V
SCL, SDA_3.3V
FRC IC
(MST7323S)
DDR2(256Mbit)
Qimonda/Hynix
FRC Block
FRC Block
LVDS
LCD Module
(FHD, 120Hz)
Overall Block Diagram
for Brazil DTV (LH70)
X-tal
12MHz
Bluetooth Module
DP1/DM1
USB_DM1
USB_DP1
DP2/DM2 
USB_DM2
USB_DP2
O.C. Protector
+5V
+5V
10. Digital TV Audio Trouble Shooting
Check video output
Y
Follow procedure All source audio 
trouble shooting
Maybe BCM3556 internal audio 
DSP has problems. Replace It
N
Follow procedure digital TV video 
trouble shooting
N
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