LG 42LA790V / 42LA790W (CHASSIS:LD34D) Service Manual ▷ View online
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Vertical Block
Source TAB IC Defect
Horizontal Block
Gate TAB IC Defect
Gate TAB IC Defect
Gate TAB IC Defect
Vertical Line
Source TAB IC Defect
Vertical Block
Source TAB IC Defect
Horizontal Block
Gate TAB IC Defect
Horizontal line
Gate TAB IC Defect
Gate TAB IC Defect
Horizontal Block
Gate TAB IC Defect
Appendix : Exchange the Module (2)
Un-repairable Cases
In this case please exchange the module.
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Standard Repair Process Detail Technical Manual
Check front display LED
B. Power error _No power
A17
Established
date
Revised
date
Error
symptom
Content
LCD TV
Front LOGO LED control in the status of
ST-BY Condition:
Menu Option LG Logo Light
Brightness(OFF,LOW,MIDDLE,HIGH)
2012. 12 .06
You can set the LG Logo Light
to on or off by selecting OPTION
in the main menus.
Front LOGO LED control in the status of
Power On Condition:
Menu Option LG Logo Light
Duration(off, off after10min)
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24 Pin
(Power Board ↔ Main Board)
SMAW200-H24S
1
Power on
2
Inverter On/off
3
3.5V
4
PWM Dim #1
5
3.5V
6
PWM Dim #2
7
GND
8
GND
9
24V
10
24V
11
GND
12
GND
13
12V
14
12V
15
12V
16
24V
17
GND
18
GND
19
GND
20
GND
21
GND
22
L/DIMO_VS
23
L/DIM0_MOSI
24
L/DIM0_SCLK
Standard Repair Process Detail Technical Manual
Check power input voltage and ST-BY 3.5V
B. Power error _No power
A18
Established
date
Revised
date
Error
symptom
Content
LCD TV
Check the DC 24V, 12V, 3.5V.
2012. 12 .06
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Standard Repair Process Detail Technical Manual
Checking method when power is ON
B. Power error _No power
A19
Established
date
Revised
date
Error
symptom
Content
LCD TV
Check “power on” pin is high
2012. 12 .06
24 Pin
(Power Board ↔ Main Board)
SMAW200-H24S
1
Power on
2
Inverter On/off
3
3.5V
4
PWM Dim #1
5
3.5V
6
PWM Dim #2
7
GND
8
GND
9
24V
10
24V
11
GND
12
GND
13
12V
14
12V
15
12V
16
24V
17
GND
18
GND
19
GND
20
GND
21
GND
22
L/DIMO_VS
23
L/DIM0_MOSI
24
L/DIM0_SCLK
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