LG 42SL90-UA (CHASSIS:LA92S) Service Manual ▷ View online
LA92S Trouble shooting guide – SPDIF
Audio(Out)
Check the output (Pin E9) of LGE3369(IC601).
Measure waveform at R656 because it’s more easy to check.
Can you see the normal signal?
Measure waveform at R656 because it’s more easy to check.
Can you see the normal signal?
Check the input of JK104.
Can you see the normal waveform?
Can you see the normal waveform?
YES
NO
NO
This board has big problem because Main chip(LGE3369) have some troubles.
After checking thoroughly all path once again, You should decide to replace LGE3369 or
After checking thoroughly all path once again, You should decide to replace LGE3369 or
After checking audio signal line, you should decide to replace item or not.
YES
After checking the Jack, you should decide to replace item or not.
D-sub RGB
HDMI 1
DDR2 (1Gbit)
Qimonda / Hynix
NAND Flash
(256Mb)
Digital Audio (Optic)
Digital AMP
NTP3000A
RS-232C (Ctrl./SVC)
I2S
EEPROM
512Kb
RGB/H/V
Hal
f-N
f-N
IM Tu
ner
DDR_Data[0:15], DQS, DM …
Addr.[ ], ctrl. data
MAX3232
Saturn6
Saturn6
(ATSC
(ATSC
US)
US)
MPEG2
Linux
Scaler
Headphone
Data [0 … 7]
IF +/-
SIF
TU_CVBS
Reset / IF_AGC …
SDA/SCL_5V
JTAG
CLK,TDI,TDO,MS,RST
HDMI3
Addr[0…1], CS …
Audio L/R
Audio L/R (for RGB)
HDMI 2
SPDIF
RX/TX
RX/TX
JACK PACK
JACK PACK
at REAR
at REAR
JACK PACK
JACK PACK
at SIDE
at SIDE
SCL, SDA_3.3V
TR Buffer
VSB
Demod.
X-tal
Reset Switch
Reset IC
12MH
z
TS In[0…7]
TS_clk, SOP, Val
TS_clk, SOP, Val
EEPROM
Data[16:31]
DDR2 (512Mbit)
Qimonda / Hynix
AV
Component 1
Y Pb Pr, L/R
CVBS, Y/C, L/R
Component 2
Y Pb Pr, L/R
Digital Audio (Coaxial)
USB2.0
SCL, SDA_3.3V
Bluetooth
Dongle
(Option)
DP/DM
DP/DM
O.C. Protector
+5V
+5V
LCD Module
(FHD, 120Hz)
FRC IC
(LGE7329A)
DDR2
Qimonda/Hynix
FRC Block
FRC Block
LVDS
LCD Module
(FHD, 60Hz)
Option
HDMI 3
HDMI S/W
I2C Map
+3.3V
NTP300A
IR(Eye-Q)
+5V_GENERAL
MST7323
(URSA)
LGDT3304
SDA_0, SCL_0
MEMC_SDA, MEMC_SCL
SDA_1, SCL_1
SDA_SUB/AMP, SCL_SUB/AMP
FE_DEMOD_SDA, FE_DEMOD_SCL
+5V_GENERAL
TUNER
FE_TUNER_SDA,
FE_TUNER_SCL
FE_TUNER_SCL
+5V_TU
OPTION
AT24C512
EEPROM_SDA,
EEPROM_SCL
EEPROM_SCL
+3.3V
SATURN6
MLINK_SDA,
MLINK_SCL
MLINK_SCL
+5V_GENERAL
PS421
(HDMI S/W)
POWER MANAGEMENT
+24V
+24V_AMP
+12V
SI4925
12V_TCON
MP2305S
+5V_EXT
KIA78R05
+5V_TUNER
+5V_TU
+5V_ST
SI4925
+5V_GENERAL
+5V
+5V_ST
AZ1117
+3.3V_ST
+3.3V_AVDD_MPLL
+3.3V_HDMI_ST
+5V
AZ1117
+3.3V_AVDD
AZ1117-1.8
+1.8V_AMP
MP2305DS
+3.3V
+3.3V_GENERAL
SC4215
+1.8V_DDR
+3.3V_FE
+3.3V_MEMC
BD9130EFJ
+1.8V_MEMC
SC4215
+1.26V_MEMC
+5V_GENERAL
AZ1117
+1.26_VDDC
SC1565
+3.3V_PVSB
+3.3V_AVDD_PVSB
SC4215
+1.2V_PVSB
+3.3V_DVDD_PVSB
+1.2V_DVDD_PVSB
+3.3V_FE
OPTION
600mA
+5V_EXT
OPTION
AS7809
+1.8V_NXP