42LV375H-ZA (CHASSIS:LD03X) - LG TV Service Manual (repair manual)

Model
42LV375H-ZA (CHASSIS:LD03X)
Pages
39
Size
4.69 MB
Type
PDF
Document
Service Manual
Brand
Device
TV / LCD
File
42lv375h-za-chassis-ld03x.pdf
Date

View LG 42LV375H-ZA (CHASSIS:LD03X) Service Manual online

LED LCD TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : LD03X
MODEL : 42LV375H
42LV375H-ZA
P/NO : MFL63263134 (1105-REV00)
- 2 -
CONTENTS
CONTENTS .............................................................................................. 2
PRODUCT SAFETY ..................................................................................3
SPECIFICATION ....................................................................................... 4
ADJUSTMENT INSTRUCTION ................................................................ 7
TROUBLE SHOOTING GUIDE................................................................14
BLOCK DIAGRAM.................................................................................. 20
EXPLODED VIEW .................................................................................. 21
SCHEMATIC CIRCUIT DIAGRAM ..............................................................
- 3 -
SAFETY PRECAUTIONS
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by      in the
Schematic Diagram and Exploded View.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent
Shock, Fire, or other Hazards. 
Do not modify the original design without permission of manufacturer.
General Guidance
An  isolation Transformer should always be used during the
servicing of a receiver whose chassis is not isolated from the AC
power line. Use a transformer of adequate power rating as this
protects the technician from accidents resulting in personal injury
from electrical shocks.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitry that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.
When replacing a high wattage resistor (Oxide Metal Film Resistor,
over 1 W), keep the resistor 10 mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Before returning the receiver to the customer,
always perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc., to
be sure the set is safe to operate without damage of electrical
shock. 
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source, connect an
electrical jumper across the two AC plug prongs. Place the AC
switch in the on position, connect one lead of ohm-meter to the AC
plug prongs tied together and touch other ohm-meter lead in turn to
each exposed metallic parts such as antenna terminals, phone
jacks, etc. 
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1 MΩ and 5.2 MΩ. 
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
Leakage Current Hot Check
(See below Figure) 
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5 K / 10 watt resistor in parallel with a 0.15 uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter
with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC voltage
measurements for each exposed metallic part. Any voltage
measured must not exceed 0.75 volt RMS which is corresponds to
0.5 mA.
In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Leakage Current Hot Check circuit
1.5 Kohm/10W
To Instrument's
exposed 
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
When 25A is impressed between Earth and 2nd Ground
for 1 second, Resistance must be less than 0.1
*Base on Adjustment standard
IMPORTANT SAFETY NOTICE
0.15 uF
- 4 -
SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement.
1. Application range
This specification is applied to the LCD TV used LD03X
chassis.
2. Requirement for Test
Each part is tested as below without special appointment.
1) Temperature: 25 ºC ± 5 ºC(77 ºF ± 9 ºF), CST: 40 ºC ± 5 ºC
2) Relative Humidity :  65 % ± 10 %
3) Power Voltage
: Standard input voltage (AC 100-240 V~, 50 / 60 Hz)
* Standard Voltage of each products is marked by models.
4) Specification and performance of each parts are followed
each drawing and specification by part number in
accordance with BOM.
5) The receiver must be operated for about 5 minutes prior to
the adjustment.
3. Test method
1) Performance: LGE TV test method followed 
2) Demanded other specification 
- Safety : CE, IEC specification
- EMC :CE, IEC 
4. Module General Specification
No.
Item
Specification
Remark
1
Display Screen Device
107 cm(42 inch) wide color display module
2
Aspect Ratio
16:9
3
LCD Module 
107 cm(42 inch) TFT LCD FHD 50 Hz
4
Operating Environment Temp. : 0 deg ~ 50 deg
Humidity : 10 % ~ 90 %
5
Storage Environment 
Temp. : -20 deg ~ 60 deg
Humidity : 10 ~ 90 %
6
Input Voltage 
AC 100-240 V~, 50 / 60 Hz
7
Power Consumption
Power on  (White)
LGD
Typ : 91.3
LCD (Module) + Backlight(EDGE LED)
8
Module Size
968.4(H) x 564(V) x 10.8(B)/18.3 mm(D)
With inverter
9
Pixel Pitch
0.4845 mm x 0.4845 mm
10
Back Light
EDGE LED
11
Display Colors
16.7 M colors
12
Coating
3H(Hard coating), AG
- 5 -
5. Module optical specification
1) Standard Test Condition (The unit has been ‘ON’)
2) Stable in a dark environment at 25 ºC ± 2 ºC.
3) Operating Ambient Humidity : Min 10, max 90 %RH
4) Ta= 25 ºC ± 2 ºC, VLCD= 12.0 V, fV= 60 Hz
No.
Item Specification 
Min.
Typ.
Max.
Remark
1.
Viewing Angle<CR>10> 
Right/Left/Up/Down
89
CR > 10
2.
Luminance Luminance 
(cd/m
2
)
290
360
Variation -
1.3
MAX 
/MIN
3.
Contrast Ratio 
CR
1000
1400
4.
CIE Color Coordinates
White
Wx
0.279 
Wy 0.292
RED
Rx
0.637
Ry
Typ.
0.341
Typ.
Green Gx
-0.03
0.325
+0.03
Gy
0.600
Blue Bx 
0.152
By  
0.051
6. Component Video Input (Y, C
B
/P
B
, C
R
/P
R
)
No.
Specification
Remark
Resolution
H-freq(kHz)
V-freq(Hz)
1.
720x480 15.73 
60.00 
SDTV,DVD 
480i
2.
720x480 15.63 
59.94 
SDTV,DVD 
480i
3.
720x480
31.47
59.94 480p
4.
720x480
31.50
60.00 480p
5.
720x576 
15.625 
50.00 
SDTV,DVD 625 Line
6.
720x576 31.25 
50.00
HDTV 
576p
7.
1280x720
45.00
50.00 HDTV 
720p
8.
1280x720
44.96
59.94 HDTV 
720p
9.
1280x720 45.00 
60.00 
HDTV 
720p
10.
1920x1080 31.25 
50.00 
HDTV 
1080i
11.
1920x1080
33.75
60.00 HDTV 
1080i
12.
1920x1080 33.72 
59.94 
HDTV 
1080i
13.
1920x1080 56.250 
50 
HDTV 
1080p
14.
1920x1080
67.5 60 HDTV 
1080p
- 6 -
No.
Specification
Proposed
Remarks
Resolution
H-freq(kHz)
V-freq(Hz)
Pixel Clock(MHz)
1.
720*400 
31.468 
70.08
28.321 
For only DOS mode
2.
640*480 
31.469 
59.94
25.17 
VESA
Input 848*480 60 Hz, 852*480 60 Hz
-> 640*480 60 Hz Display
3.
800*600
37.879
60.31
40.00 VESA 
4.
1024*768 48.363 60.00
65.00 VESA(XGA) 
5.
1280*768 47.78 59.87
79.5 
WXGA 
 
6.
1360*768 47.72
59.8
84.75 
WXGA
7.
1280*1024 63.595  60.0 
108.875
SXGA
FHD 
model
8.
1920*1080 66.587
59.93
138.625  WUXGA
FHD 
model
7. RGB (PC)
8. HDMI Input
(1) DTV Mode
No.
Resolution
H-freq(kHz)
V-freq.(Hz)
Pixel clock(MHz)
Proposed
Remark
1.
720*400 31.468 
70.08 
28.321 
HDCP
2.
640*480 31.469 
59.94 
25.17
VESA  HDCP
3. 800*600
37.879
60.31 
40.00 
VESA 
HDCP
4.
1024*768
48.363
60.00 65.00 
VESA(XGA)
HDCP
5.
1280*768 47.78
59.87
79.5
WXGA  HDCP
6.
1360*768 47.72 59.8 84.75
WXGA  HDCP
7.
1280*1024 63.595
60.0  108.875  SXGA
HDCP/FHD 
model
8.
1920*1080 67.5 
60.00
138.625  WUXGA
HDCP/FHD 
model
(2) PC Mode
No.
Resolution
H-freq(kHz)
V-freq.(Hz)
Pixel clock(MHz)
Proposed
Remark
1.
720*480 
31.469 /31.5 
59.94 /60
27.00/27.03
SDTV 480P
2.
720*576 31.25 
50
54 
SDTV 
576P
3.
1280*720 37.500 
50
74.25 
HDTV 
720P
4.
1280*720 
44.96 /45 
59.94 /60
74.17/74.25 
HDTV 720P
5.
1920*1080 
33.72 /33.75 
59.94 /60
74.17/74.25 
HDTV 1080I
6.
1920*1080 28.125 50.00
74.25 
HDTV 
1080I
7.
1920*1080 
26.97 /27 
23.97 /24
74.17/74.25 
HDTV 1080P
8.
1920*1080
33.716 /33.75
29.976 /30.00
74.25
HDTV 1080P
9.
1920*1080 56.250 50
148.5
HDTV 
1080P
10.
1920*1080 
67.43 /67.5 
59.94 /60
148.35/148.50 
HDTV 1080P
- 7 -
ADJUSTMENT INSTRUCTION
1. Application Range
This specification sheet is applied to all of the LCD TV with
LD03X chassis.
2. Designation
(1) Because this is not a hot chassis, it is not necessary to use
an isolation transformer. However, the use of isolation
transformer will help protect test instrument.
(2) Adjustment must be done in the correct order. 
(3) The adjustment must be performed in the circumstance of
25 ºC ± 5 ºC of temperature and 65 % ±10 % of relative
humidity if there is no specific designation. 
(4) The input voltage of the receiver must keep AC 100-240
V~, 50 / 60Hz.
(5) The receiver must be operated for about 5 minutes prior to
the adjustment when module is in the circumstance of over
15.
In case of keeping module is in the circumstance of 0 °C, it
should be placed in the circumstance of above 15 °C for 2
hours 
In case of keeping module is in the circumstance of below -
20 °C, it should be placed in the circumstance of above 15
°C for 3 hours.
[Caution] 
When still image is displayed for a period of 20 minutes or
longer (especially where W/B scale is strong. Digital pattern
13ch and/or Cross hatch pattern 09ch), there can some
afterimage in the black level area.
3. Automatic Adjustment
3.1. ADC Adjustment
(1) Overview
ADC adjustment is needed to find the optimum black level
and gain in Analog-to-Digital device and to compensate
RGB deviation.
(2) Equipment & Condition
1) Jig (RS-232C protocol)
2) MSPG-925 Series Pattern Generator(MSPG-925FA,
pattern - 65)
- Resolution : 480i Comp1
1080p Comp1
1080p RGB
- Pattern : Horizontal 100% Color Bar Pattern
- Pattern level : 0.7 ± 0.1 Vp-p
- Image
(3) Adjustment
1) Adjustment method
- Using RS-232, adjust items in the other shown in
“3.1.(3).3)”
2) Adj. protocol
Ref.) ADC Adj. RS232C Protocol_Ver1.0
3) Adj. order
- aa 00 00  [Enter ADC adj. mode]
- xb 00 40  [Change input source to Component1(No action)]
- ad 00 10  [Adjust 480i Comp1]
- ad 00 10  [Adjust 1080p Comp1]
- xb 00 60  [Change input source to RGB(No action)]
- ad 00 10  [Adjust 1080p RGB]
- ad 00 90  End adj.
3.2. MAC Address 
(1) Equipment & Condition
- Play file: Serial.exe
- MAC Address edit
- Input Start / End MAC address 
(2) Download method
1) Communication Prot connection
Connect: PCBA Jig-> RS-232C Port== PC-> RS-232C Port
 
PCBA 
PC(RS-232C)
 
RS-232C Po rt
 
Protocol
Command
Set ACK
Enter adj. mode
aa 00 00
a 00 OK00x
Source change
xb 00 40
b 00 OK40x (Adjust 480i, 1080p Comp1 )
xb 00 60 
b 00 OK60x (Adjust 1920*1080 RGB)
Begin adj.
ad 00 10
Return adj. result
OKx (Case of Success)
NGx (Case of Fail)
Read adj. data
(main)
(main : component1 480i, RGB 1080p)
ad 00 20 
000000000000000000000000007c007b006dx
(main)
(main : component1 1080p)
ad 00 30
000000070000000000000000007c00830077x
Confirm adj.
ad 00 99
NG 03 00x (Fail)
NG 03 01x (Fail)
NG 03 02x (Fail)
OK 03 03x (Success)
End adj.
aa 00 90
a 00 OK90x
- 8 -
2) MAC Address Download
- Com 1,2,3,4 and 115200(Baud rate)
- Click “Port connection” button(1).
- Click “Load” button(2) for MAC Address write.
- Click “MAC Address write” button(3)
- Check the OK Or NG.
3.3. LAN
(1) Equipment & Condition
A
Each other connection to LAN Port of IP Hub and Jig
(2) LAN inspection solution
A
LAN Port connection with PCB
A
Network setting at MENU Mode of Installation Menu
- “In-start” key input -> “menu” key input -> Installation
Menu
- Network Setup -> Network Setting --> Press “Enter” ->
IP Auto Setting -> OK
A
setting automatic IP
A
Setting state confirmation
-> If automatic setting is finished, you confirm IP and
MAC Address.
3.4. LAN PORT INSPECTION(PING TEST)
Connect SET -> LAN port == PC -> LAN Port
(1) Equipment setting
1) Play the LAN Port Test PROGRAM.
2) Input IP set up for an inspection to Test Program.
*IP Number : 12.12.2.2
(2) LAN PORT inspection  (PING TEST)
1) Play the LAN Port Test Program.
2) Connect each other LAN Port Jack.
3) Play Test (F9) button and confirm OK Message.
4) Remove LAN cable.
3.5. Model name & serial number download
(1) Model name & Serial number D/L
A
Press “Power on” key of service remote control.
(Baud rate : 115200 bps)
A
Connect RS232 Signal Cable to RS-232 Jack.
A
Write Serial number by use RS-232.
A
Must check the serial number at Instart menu. 
(2) Method & notice
A. Serial number D/L is using of scan equipment.
B. Setting of scan equipment operated by Manufacturing
Technology Group.
C.Serial number D/L must be conformed when it is
produced in production line, because serial number D/L
is mandatory by D-book 4.0.
* Manual Download (Model Name and Serial Number)
If the TV set is downloaded by OTA or service man, sometimes
model name or serial number is initialized.(Not always)
There is impossible to download by bar code scan, so It
need Manual download.
a. Press the ‘Instart’ key of Adjustment remote control.
b. Go to the menu ‘5.Model Number D/L’ like below photo.
c. Input the Factory model name(ex 42LD450-ZA) or Serial
number like photo.
d. Check the model name Instart menu. -> Factory name
displayed. (ex 42LE7500-ZA)
e. Check the Diagnostics. (DTV country only) -> Buyer
model displayed. (ex 42LE7500-ZA)
Commercial MENU
SET
PC
- 9 -
4. Check Commercial Features
4.1. External SPK Out and Volume control
4.1.1. Equipment & Condition
- Jig(Speaker out JIG, Speaker out control Jig) or Oscilloscope
- Power only mode
4.1.2. Check the speaker out & control
1) Connect the External Speaker : Check the sound.
2) Press the “+” key on the control Jig : Check the Max output.
3) Press the “-” key on the control Jig : Check the Min output.
Connect oscilloscope, you can see this waveform.
4.2. IR Out and DC Power Outlet(5 V / 12 V)
4.2.1. Equipment & Condition
- Jig (commercial check JIG) 
- Special 232C Cable for commercial check Jig
- Power only mode
4.2.2. Check the power out & IR out - commercial
check jig
1) Connect each other RS232C port on the Commercial Check
JIG.
2) Press RED Color key on Service remote control.
3) Check the LED of jig board.
- +12V / +5V LED (OK condition: Turn On)
- IR LED (OK condition: blinking)
4.2.3. Check the power out & IR out - mini jig
1) Connect mini jig on RS232c port.
2) Press RED Color key on Service remote control.
3) Check the LED of mini jig.
4.3. Pro:Idiom
1) Connect the RF Cable.
2) Turn to the Pro:Idiom channel (No. 333).
3) Check the video & sound.
** Only displayed at “POWER ONLY” mode
4.4. Front LED Clock
1) Check the LED Clock in Power only mode.
Button of Vol. control 
Waveform of Oscilloscope 
UP(+)
 
DOWN(-)
Recommended Input Signal
: RF, 1 KHz, Sine wave
5. Manual Adjustment
5.1. ADC Adjustment
5.1.1. Overview
ADC adjustment is needed to find the optimum black level and
gain in Analog-to-Digital device and to compensate RGB
deviation.
5.1.2. Equipment & Condition
(1) Adjustment remote coontrol
(2) 801GF(802B, 802F, 802R) or MSPG925FA Pattern Generator
- Resolution :
480i, Comp1 (MSPG-925FA: Model-209, Pattern-65)
1080p Comp1 (MSPG-925FA: Model: 225, Pattern-65)’
1080p RGB (MSPG-925FA: Model-225, Pattern-65)
- Pattern : Horizontal 100% Color Bar Pattern
- Pattern level: 0.7 ± 0.1 Vp-p
-  Image
(3) Must use standard cable
5.1.3. Adjust method
(1) ADC 480i/1080p Comp1, RGB
1) Check connected condition of Comp1 cable to the
equipment.
2) Give a 480i, Horizontal 100% Color Bar Pattern to
Comp1.(MSPG-925FA -> Model: 209, Pattern: 65)
3) Change input mode as Component1 and picture mode
as “Standard”.
4) Press the In-start Key on the ADJ remote control after at
least 1 min of signal reception. Then, select ‘7. External
ADC’. And press OK or Right key for going to sub menu.
5) Press OK in Comp 480i menu.
6) Give a 1080p Mode, Horizontal 100% Color Bar Pattern
to Comp1. (MSPG-925A -> Model: 225, Pattern: 65)
7) Press OK in Comp 1080p menu.
8) Press OK in RGB menu.
9) If ADC Comp is successful, “ADC Component Success”
is displayed.
If ADC calibration is failure, “ADC Component Fail” is
displayed.
10) If ADC calibration is failure, after recheck ADC pattern
or condition, retry calibration
11) If ADC RGB is successful, “ADC RGB Success” is
displayed. If ADC calibration is failure, “ADC RGB Fail”
is displayed.
12) If ADC calibration is failure, after recheck ADC pattern
or condition, retry calibration Error message refer to 5).
5.2. EDID(The Extended Display Identification
Data)/DDC(Display Data Channel) download
(1) Overview
It is a VESA regulation. A PC or a MNT will display an
optimal resolution through information sharing without any
necessity of user input. It is a realization of “Plug and Play”.
(2) Equipment
- Since embedded EDID data is used, EDID download JIG,
HDMI cable and D-sub cable are not need.
- Adjustment remote control
(3) Download method
1) Press ADJ key on the Adjustment remote control
2) Select EDID D/L menu.
3) By pressing Enter key, EDID download will begin.
4) If Download is successful, OK is display, but If
Download is failure, NG is displayed.
5) If Download is failure, Re-try download.
<Caution> 
When EDID Download, must remove RGB/HDMI Cable.
(4) EDID DATA
A
HDMI
A
RGB
- 10 -
D-sub to D-sub
DVI-D to HDMI or HDMI to HDMI
For HDMI EDID
For Analog EDID
0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09 0x0A 0x0B 0x0C 0x0D 0x0E 0x0F
0x00 00
FF
FF
FF
FF
FF
FF
00
1E
6D
0x01        
01
03
80
10
09
78
0A
EE
91
A3
54
4C
99
26
0x02 0F
50
54
A1
08
00
71
4F
81
80
01
01
01
01
01
01
0x03 01
01
01
01
01
01
02
3A
80
18
71
38
2D
40
58
2C
0x04 45
00
A0
5A
00
00
00
1E
01
1D
00
72
51
D0
1E
20
0x05 6E
28
55
00
A0
5A
00
00
00
1E
00
00
00
FD
00
3A
0x06 3E
1E
53
10
00
0A
20
20
20
20
20
20
0x07
01
0x00 02
03
26
F1
4E
10
1F
84
13
05
14
03
02
12
20
21
0x01 22
15
01
26
15
07
50
09
57
07
67
0x02
E3
05
03
01
01
1D
80
18
71
1C
16
20
58
2C
0x03 25
00
A0
5A
00
00
00
9E
01
1D
00
80
51
D0
1A
20
0x04 6E
88
55
00
A0
5A
00
00
00
1A
02
3A
80
18
71
38
0x05 2D
40
58
2C
45
00
A0
5A
00
00
00
1E
66
21
50
B0
0x06 51
00
1B
30
40
70
36
00
A0
5A
00
00
00
1E
00
00
0x07 00
00
00
00
00
00
00
00
00
00
00
00
00
00
01
ⓔ2
0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09 0x0A 0x0B 0x0C 0x0D 0x0E 0x0F
0x00 00
FF
FF
FF
FF
FF
FF
00
1E
6D
0x01        
01
03
68
10
09
78
0A
EE
91
A3
54
4C
99
26
0x02 0F
50
54
A1
08
00
81
80
61
40
45
40
31
40
01
01
0x03 01
01
01
01
01
01
02
3A
80
18
71
38
2D
40
58
2C
0x04 45
00
A0
5A
00
00
00
1E
01
1D
00
72
51
D0
1E
20
0x05 6E
28
55
00
A0
5A
00
00
00
1E
00
00
00
FD
00
3A
0x06 3E
1E
53
10
00
0A
20
20
20
20
20
20
0x07
00
ⓔ3

Download LG 42LV375H-ZA (CHASSIS:LD03X) Service Manual (Repair Manual)

Here you can view online and download LG 42LV375H-ZA (CHASSIS:LD03X) Service Manual in PDF. 42LV375H-ZA (CHASSIS:LD03X) service manual will guide through the process and help you recover, restore, fix, disassemble and repair LG 42LV375H-ZA (CHASSIS:LD03X) LCD. Information contained in service manuals typically includes schematics / circuit diagrams, wiring diagrams, block diagrams, printed wiring boards, exploded views, parts list, disassembly / assembly, pcb.