LG 19LH20 (CHASSIS:LA92A) Service Manual ▷ View online
C
2009
- 17 -
6. AV Video
Check AV Cable for damage or open conductor.
Check JK1200(*JK1202).
OK
Check input signal format.
Is it supported?
OK
Replace Jack.
*JK1202 is Side AV supported model
32/37/42/47LH30 Models
No
OK
Check Mstar LVDS output
Replace Mstar(IC100) or Main board.
No
Check HDMI Cable conductors for
damage of open conductor.
Check JK500, 501, 502
OK
OK
Check input signal format.
Is it supported?
OK
Check EDID & EEPROM
IC500, 501, 502.
I2C Signal
Replace Jack.
No
Replace the defective IC or re-download
EDID data.
No
Check HDCP key NVRAM(IC105)
power & I2C Signal (#5, #6)
Replace the defective IC.
No
OK
Check HDMI Signal
Check other set.
If no problem, check signal line.
No
Replace Main board.
No
OK
7. HDMI Video
OK
Check Mstar LVDS output
Replace Mstar(IC100) or Main board.
No
C
2009
- 18 -
8. All Source Audio
Check Mstar I2S Output
R604, R605, R606
Check IC600 Power
*20V, 3.3V, 1.8V.
OK
OK
Make sure you can’t hear any audio.
OK
First check the TV SPEAKER Menu
(Menu > Sound > TV Speaker)
Toggle the menu.
OK
Check Mstar AUDIO_MASTER_CLK
R603
OK
Check Connector & P600
Check Regulator IC601, IC704
No
Check signal line. Or replace IC100.
No
Replace Mstar(IC100) or Main board.
No
No
Check Output Signal P600 1, 2, 3, 4 pin.
OK
Replace NTP(Audio AMP)
IC500.
No
Replace connector if found to be damaged.
No
OK
Check speaker resistance
and connector damage.
Replace speaker.
No
*20V Voltage is dependent on model.
32/36LH20, 32LH30 => 24V
19/22LH20 => 15V(pin1 or 2)
C
2009
- 19 -
10. Analog TV Audio
Check RF Cable.
OK
Check SIF buffer signal.
Check SIF Signal line.
No
OK
Check Tuner 5V Power
TU1001 4pin
Check IC1002.
Check IC1005(19”, 22”).
No
Bad Tuner
Replace Tuner.
No
OK
Follow procedure All source audio
trouble shooting guide.
Replace Mstar(IC100)
or Main board.
No
9. Digital TV Audio
Check Tuner 5V Power
TU1001 4pin.
Check IC1002.
Check IC1005(19”, 22”)
No
OK
Check IF_P/N Signal.
Bad Tuner. Replace Tuner
No
OK
Check Demodulator Input Clock(X1005).
Replace X1005.
No
OK
Check IC400(LGDT) Output
-AR1070, AR1071
Replace IC400.
No
OK
Check Output Signal
P600 1, 2, 3, 4 pin
Replace NTP(Audio AMP)
IC500
No
OK
Check speaker resistance
and connector damage.
Replace speaker.
No
OK
Check Connector & P600
Replace connector
if found to be damaged.
No
C
2009
- 20 -
BLOCK DIAGRAM
D-sub RGB
HDMI 1
Side AV
CVBS, L/R
DDR2 (512Mbit)
Qimonda /
Hynix
NAND Flash
(256Mb)
Digital Audio (Optic)
Digital AMP
NTP3100L
RS-232C (Ctrl./SVC)
I2S
EEPROM
512Kb
RGB/H/V
Half-NIM Tuner
DDR_Data[0:15], DQS, DM...
Addr.[ ], ctrl. data
MAX3232
Saturn5
(ATSC
US)
MPEG2
Linux
Scaler
Data [0...7]
IF +/-
SIF
TU_CVBS
Reset / IF_AGC...
SDA/SCL_5V
JTAG
CLK,TDI,TDO,MS,RST
Addr[0...1], CS...
Audio L/R
Audio L/R (for RGB)
HDMI 2
SPDIF
RX/TX
RX/TX
JACK PACK
at REAR
JACK PACK
at SIDE
SCL, SDA_3.3V
TR Buffer
VSB
Demod
.
LGDT3305
X-tal
Reset Switch
Reset IC
12MHz
TS In[0...7
]
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
SCL, SDA_3.3V
Bluetooth
Dongle
(Option)
DP/DM
LCD Module
(FHD,HD)
LVDS
EEPROM
EEPROM
HDMI 3
EEPROM
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