LG 22LF4520-PU User manual

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Europe/Africa http://eic.lgservice.com
Asia/Oceania http://biz.lgservice.com
Internal Use Only
Printed in KoreaP/NO :
CHASSIS :
MODEL :
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
SERVICE MANUAL
MFL68920123 (1501-REV00)
22LF4520 22LF4520-PU
LU50A
LED TV

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Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
CONTENTS
CONTENTS .............................................................................................. 2
SAFETY PRECAUTIONS ......................................................................... 3
SERVICING PRECAUTIONS.................................................................... 4
SPECIFICATION ....................................................................................... 6
ADJUSTMENT INSTRUCTION ................................................................ 9
TROUBLE SHOOTING........................................................................... 13
BLOCK DIAGRAM.................................................................................. 17
EXPLODED VIEW .................................................................................. 18
SCHEMATIC CIRCUIT DIAGRAM ........................................... APPENDIX

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Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
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 1W), keep the resistor 10mm 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 1MΩand 5.2MΩ.
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 1.5K/10watt resistor in parallel with a 0.15uF 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
0.5mA.
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
0.15µF
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
SAFETY PRECAUTIONS

- 4 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
CAUTION: Before servicing receivers covered by this service
manual and its supplements and addenda, read and follow the
SAFETY PRECAUTIONS on page 3 of this publication.
NOTE: If unforeseen circumstances create conflict between the
following servicing precautions and any of the safety precautions on
page 3 of this publication, always follow the safety precautions.
Remember: Safety First.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power
source before;
a. Removing or reinstalling any component, circuit board
module or any other receiver assembly.
b. Disconnecting or reconnecting any receiver electrical plug or
other electrical connection.
c. Connecting a test substitute in parallel with an electrolytic
capacitor in the receiver.
CAUTION: A wrong part substitution or incorrect polarity
installation of electrolytic capacitors may result in an
explosion hazard.
2. Test high voltage only by measuring it with an appropriate high
voltage meter or other voltage measuring device (DVM,
FETVOM, etc) equipped with a suitable high voltage probe.
Do not test high voltage by "drawing an arc".
3. Do not spray chemicals on or near this receiver or any of its
assemblies.
4. Unless specified otherwise in this service manual, clean
electrical contacts only by applying the following mixture to the
contacts with a pipe cleaner, cotton-tipped stick or comparable
non-abrasive applicator; 10% (by volume) Acetone and 90% (by
volume) isopropyl alcohol (90%-99% strength)
CAUTION: This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of
contacts in not required.
5. Do not defeat any plug/socket B+ voltage interlocks with which
receivers covered by this service manual might be equipped.
6. Do not apply AC power to this instrument and/or any of its
electrical assemblies unless all solid-state device heat sinks are
correctly installed.
7. Always connect the test receiver ground lead to the receiver
chassis ground before connecting the test receiver positive
lead.
Always remove the test receiver ground lead last.
8. Use with this receiver only the test fixtures specified in this
service manual.
CAUTION: Do not connect the test fixture ground strap to any
heat sink in this receiver.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid-state) devices can be damaged easily
by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES
devices are integrated circuits and some field-effect transistors and
semiconductor "chip" components. The following techniques
should be used to help reduce the incidence of component
damage caused by static by static electricity.
1. Immediately before handling any semiconductor component or
semiconductor-equipped assembly, drain off any electrostatic
charge on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed to
prevent potential shock reasons prior to applying power to the
unit under test.
2. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such as
aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES
devices.
4. Use only an anti-static type solder removal device. Some solder
removal devices not classified as "anti-static" can generate
electrical charges sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective
package until immediately before you are ready to install it.
(Most replacement ES devices are packaged with leads
electrically shorted together by conductive foam, aluminum foil
or comparable conductive material).
7. Immediately before removing the protective material from the
leads of a replacement ES device, touch the protective material
to the chassis or circuit assembly into which the device will be
installed.
CAUTION: Be sure no power is applied to the chassis or circuit,
and observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Otherwise harmless motion such as
the brushing together of your clothes fabric or the lifting of your
foot from a carpeted floor can generate static electricity
sufficient to damage an ES device.)
General Soldering Guidelines
1. Use a grounded-tip, low-wattage soldering iron and appropriate
tip size and shape that will maintain tip temperature within the
range or 500 ˚F to 600 ˚F.
2. Use an appropriate gauge of RMA resin-core solder composed
of 60 parts tin/40 parts lead.
3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use a mall wire-
bristle (0.5 inch, or 1.25cm) brush with a metal handle.
Do not use freon-propelled spray-on cleaners.
5. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.
(500 ˚F to 600 ˚F)
b. Heat the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction-
type solder removal device or with solder braid.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
6. Use the following soldering technique.
a. Allow the soldering iron tip to reach a normal temperature
(500 ˚F to 600 ˚F)
b. First, hold the soldering iron tip and solder the strand against
the component lead until the solder melts.
c. Quickly move the soldering iron tip to the junction of the
component lead and the printed circuit foil, and hold it there
only until the solder flows onto and around both the
component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
d. Closely inspect the solder area and remove any excess or
splashed solder with a small wire-bristle brush.
SERVICING PRECAUTIONS

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Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong) through
which the IC leads are inserted and then bent flat against the
circuit foil. When holes are the slotted type, the following technique
should be used to remove and replace the IC. When working with
boards using the familiar round hole, use the standard technique
as outlined in paragraphs 5 and 6 above.
Removal
1. Desolder and straighten each IC lead in one operation by gently
prying up on the lead with the soldering iron tip as the solder
melts.
2. Draw away the melted solder with an anti-static suction-type
solder removal device (or with solder braid) before removing the
IC.
Replacement
1. Carefully insert the replacement IC in the circuit board.
2. Carefully bend each IC lead against the circuit foil pad and
solder it.
3. Clean the soldered areas with a small wire-bristle brush.
(It is not necessary to reapply acrylic coating to the areas).
"Small-Signal" Discrete Transistor
Removal/Replacement
1. Remove the defective transistor by clipping its leads as close as
possible to the component body.
2. Bend into a "U" shape the end of each of three leads remaining
on the circuit board.
3. Bend into a "U" shape the replacement transistor leads.
4. Connect the replacement transistor leads to the corresponding
leads extending from the circuit board and crimp the "U" with
long nose pliers to insure metal to metal contact then solder
each connection.
Power Output, Transistor Device
Removal/Replacement
1. Heat and remove all solder from around the transistor leads.
2. Remove the heat sink mounting screw (if so equipped).
3. Carefully remove the transistor from the heat sink of the circuit
board.
4. Insert new transistor in the circuit board.
5. Solder each transistor lead, and clip off excess lead.
6. Replace heat sink.
Diode Removal/Replacement
1. Remove defective diode by clipping its leads as close as
possible to diode body.
2. Bend the two remaining leads perpendicular y to the circuit
board.
3. Observing diode polarity, wrap each lead of the new diode
around the corresponding lead on the circuit board.
4. Securely crimp each connection and solder it.
5. Inspect (on the circuit board copper side) the solder joints of
the two "original" leads. If they are not shiny, reheat them and if
necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
1. Clip each fuse or resistor lead at top of the circuit board hollow
stake.
2. Securely crimp the leads of replacement component around
notch at stake top.
3. Solder the connections.
CAUTION: Maintain original spacing between the replaced
component and adjacent components and the circuit board to
prevent excessive component temperatures.
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit
board will weaken the adhesive that bonds the foil to the circuit
board causing the foil to separate from or "lift-off" the board. The
following guidelines and procedures should be followed whenever
this condition is encountered.
At IC Connections
To repair a defective copper pattern at IC connections use the
following procedure to install a jumper wire on the copper pattern
side of the circuit board. (Use this technique only on IC
connections).
1. Carefully remove the damaged copper pattern with a sharp
knife. (Remove only as much copper as absolutely necessary).
2. carefully scratch away the solder resist and acrylic coating (if
used) from the end of the remaining copper pattern.
3. Bend a small "U" in one end of a small gauge jumper wire and
carefully crimp it around the IC pin. Solder the IC connection.
4. Route the jumper wire along the path of the out-away copper
pattern and let it overlap the previously scraped end of the good
copper pattern. Solder the overlapped area and clip off any
excess jumper wire.
At Other Connections
Use the following technique to repair the defective copper pattern
at connections other than IC Pins. This technique involves the
installation of a jumper wire on the component side of the circuit
board.
1. Remove the defective copper pattern with a sharp knife.
Remove at least 1/4 inch of copper, to ensure that a hazardous
condition will not exist if the jumper wire opens.
2. Trace along the copper pattern from both sides of the pattern
break and locate the nearest component that is directly
connected to the affected copper pattern.
3. Connect insulated 20-gauge jumper wire from the lead of the
nearest component on one side of the pattern break to the lead
of the nearest component on the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed so the
it does not touch components or sharp edges.

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SPECIFICATION
1. Application Range
This spec sheet is applied all of the TV used LU50A chassis.
2. Specication
Each part is tested as below without special appointment
1) Temperature : 25 ˚C ± 5 ˚C (77 ˚F ± 9 ˚F),
CST : 40 ˚C ± 5 ˚C
2) Relative Humidity : 65 % ± 10 %
3) Power Voltage : Standard input voltage
(100 V - 240 V ~, 50 / 60 Hz)
· Standard Voltage of each products is marked by mod-
els
4) Specication and performance of each parts are followed
each drawing and specication by part number in accord-
ance 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 specication
- Safety : UL
- EMI : FCC
NOTE : Specications and others are subject to change without notice for improvement.
4. General specication
4.1. TV
4.2. Feature and Function
No Item Specication Remarks
1 Market MEXICO
2 Available Channel 1)Digital : ATSC
2)Analog : NTSC
3 Receiving system ATSC / NTSC-M
4 Interface RF / Composite(CVBS) / Component / HDMI / D-Sub / USB
No Item Specication Remarks
1 RF Input Analog NTSC
DTV ATSC
2 HDMI Input (Rear) HDMI version 1.4/ support PC
Support HDCP
Rear : 1EA
3 Component Input
(Rear, 1EA)
Y/Pb/Pr
4 CVBS Input ATSC/NTSC-M common port with Component.
5 USB (Side, 1EA) For My Media(Photo/Music List) Picture + Music

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Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
5. External Input Support Format
- RGB/HDMI (PC)
No. Resolution H-freq(kHz) V-freq(Hz) Pixel clock(MHz) Remark
1 720*400 31.468 70.080 28.321
2 640*480 31.469 59.940 25.175
3 640*480 37.500 75.000 31.500
4 800*600 37.879 60.317 40.000
5 800*600 46.875 75.000 49.500
6 1024*768 48.363 60.004 65.000
7 1024*768 56.476 70.069 75.000 HDMI(PC)
8 1024*768 60.023 75.029 78.750
9 1152*864 67.500 75.000 108.000
10 1280*720 45.000 60.000 74.250
11 1280*800 49.702 59.810 83.500
12 1280*1024 63.981 60.020 108.000
13 1280*1024 79.976 75.025 135.000
14 1400*1050 65.317 59.978 121.750
15 1440*900 55.935 59.887 106.500
16 1600*900 60.000 60.000 108.000
17 1680*1050 64.674 59.883 119.000
18 1680*1050 65.290 59.954 146.250
19 1920*1080 67.500 60.000 148.500
- HDMI (DTV)
No. Resolution H-freq(kHz) V-freq(Hz) Pixel clock(MHz) Remark
1 720* 480 31.469 / 31.5 59.94 / 60 27.00/ 27.03 SDTV 480P
2 720*576 31.25 50.00 27.864 SDTV 576P
3 1280*720 37.50 50.00 74.250 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 27.00 24 74.25 HDTV 1080P
8 1920* 1080 33.75 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

- 8 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
- Component
No Specication Remark
Resolution H-freq(kHz) V-freq(Hz)
1 720x480 15.73 59.84 720x480i
2 15.73 60
3 720x480 31.47 59.84 720x480p
4 31.5 60
5 1280x720 44.96 59.84 1280x720p
6 45 60
7 1920x1080 33.72 59.84 1920x1080i
8 33.75 60
9 26.97 23.976 1920x1080p
10 27 24
11 33.71 29.97
12 33.75 30
13 67.432 59.84
14 67.5 60

- 9 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
ADJUSTMENT INSTRUCTION
1. Application Range
This document is applied to LU50A chassis TV which is manu-
factured in TV (or Monitor) Factory or is produced on the basis
of this data.
2. Designation
1) The adjustment is according to the order which is designat-
ed and which must be followed, according to the plan which
can be changed only on agreeing.
2) Power adjustment : Free Voltage.
3) Magnetic Field Condition: Nil.
4) Input signal Unit: Product Specication Standard.
5) Reserve after operation: Above 5 Minutes (Heat Run)
Temperature : at 25 °C ± 5 °C
Relative humidity : 65 % ± 10 %
Input voltage : 220 V, 60 Hz
6) Adjustment equipments : Color Analyzer (CA-210 or CA-
110), DDC Adjustment Jig equipment, SVC remote control-
ler.
7) Push The "IN STOP KEY" – For memory initialization
3. Main PCB check process
* APC - After Manual-Insult, executing APC
* Boot le Download
1) Execute ISP program “Mstar ISP Utility” and then click
“Cong” tab.
2) Set as below, and then click “Auto Detect” and check “OK”
message. If display “Error”, Check connect computer, jig,
and set.
3) Click “Connect” tab. If display “Can’t ”, Check connect
computer, jig, and set.
*When you use JIG for checking and download. Connect D-
SUB cable D-SUB jack for RS232. (Refer to 12page)
4) Click “Read” tab, and then load download le(XXXX.bin) by
clicking “Read”
5) Click “Auto” tab and set as below
6) Click “Run”.
7) After downloading, check “OK” message.
* USB DOWNLOAD
1) Make New folder named “LG_DTV” and put ISP le(*.bin)
in the folder.
2) Put the USB Stick to the USB socket.
3) 3 Automatically detecting update le in USB Stick
- If your downloaded program version in USB Stick is
Low, it didn’t work. But your downloaded version is
High, USB data is automatically detecting.
4) TV Software Upgrade feature will be displayed.
5) Updating is starting.
6) Updating Completed, The TV will restart automatically.
(1) (3)
(
2
)
OK
Please Check the Speed :
Use the speed under
200KHz.
(4)
filexxx.bin
(
6
)
(5)
(7) ……….OK
(
5
)
Case1 : Software version up
1) After downloading S/W by USB , Multi-vision set will
reboot automatically
2) Push "In-stop" key
3) Push "Power on" key
4) Function inspection
5) After function inspection, Push "In-stop" key.
Case2 : Function check at the assembly line
1) When TV set is entering on the assembly line, Push "In-
stop" ke y at rst.
2) Push "Power on" key for turning it on.
→ If you push "Power on" key, TV set will recover channel
information by itself.
3) After function inspection, Push "In-stop" key.

- 10 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
3.1. EDID Process
3.1.1. EDID download
1) Press “Power only” key of service remote controller.
2) Press the “ADJ” Key of service remote controller.
3) Enter EDID D/L mode by pushing “►” key at “EDID D/L”.
4) Select “Start” menu to download EDID data.
5) Check the “OK” message.
6) Press EXIT key on R/C.
→ Caution: Do not connect HDMI Cable when download
EDID
* Edid data and Model option download (RS232)
→ Caution
* Use the proper signal cable for EDID Download
- Analog EDID : Pin3 exists
- Digital EDID : Pin3 exists
3.1.2. EDID Data
- RGB : Check sum : BC
- HDMI : Checksum : 13 F0
3.2. Function Check
3.2.1. Check display and sound
*Check Input and Signal items. (cf. work instructions)
1) TV
2) 2) AV (SCART/CVBS)
3) COMPONENT (480i)
4) HDMI
* Display and Sound check is executed by Remote controller.
→ Caution : Not to push the INSTOP KEY after completion if
the function inspection.
NO Item CMD
1
CMD
2
Data 0
Enter
download
MODE
Download
‘Mode In’
A A 0 0 When transfer the
‘Mode In’,
Carry the command.
EDID data and
Model option
download
Download A E 00 10 Automatically download
(The use of a internal
Data)
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0
0
FF
FF
FF
FF
FF
FF
0
1E
6D
C6
59
1
1
1
1
10
1
19
1
3
80
33
1D
78
EA
62
75
A3
55
4F
A0
27
20
12
50
54
A5
6F
0
71
4F
81
C0
81
0
81
80
95
0
30
90
40
A9
C0
B3
0
2
3A
80
18
71
38
2D
40
58
2C
40
45
0
FD
1E
11
0
0
1A
21
39
90
30
62
1A
27
40
50
68
B0
36
0
FD
1E
11
0
0
1C
0
0
0
FD
0
38
60
4B
1E
53
0F
0
0A
20
20
20
20
20
20
0
0
0
FC
70
0
32
44
20
46
48
44
20
4C
47
20
54
56
0A
1
13
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0
2
3
1E
F1
4E
84
5
3
2
20
22
10
11
13
12
14
10
1F
7
16
23
9
57
7
66
3
0C
0
10
0
80
1
1D
20
0
72
51
D0
1E
20
38
88
15
0
56
50
21
0
0
1E
30
1
1D
80
18
71
1C
16
20
58
2C
25
0
56
50
21
0
40
0
9E
1
1D
80
D0
72
1C
16
20
10
2C
25
80
C4
8E
50
21
0
0
9E
2
3A
80
D0
72
38
2D
40
10
2C
45
20
60
6
44
21
0
0
1E
2
3A
80
18
71
38
2D
40
58
2C
70
45
0
56
50
21
0
0
1E
0
0
0
0
0
0
0
F0
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0
0
FF
FF
FF
FF
FF
FF
0
1E
6D
C4
59
1
1
1
1
10
1
19
1
3
68
33
1D
78
EA
62
75
A3
55
4F
A0
27
20
12
50
54
A5
6B
80
71
4F
81
C0
81
0
81
80
95
0
30
90
40
A9
C0
B3
0
2
3A
80
18
71
38
2D
40
58
2C
40
45
0
FD
1E
11
0
0
1A
0
0
0
FD
0
38
4B
1E
50
53
0F
0
0A
20
20
20
20
20
20
0
0
0
FC
0
32
60
44
20
46
48
44
20
4C
47
20
54
56
0A
0
0
0
FF
70
0
0A
20
20
20
20
20
20
20
20
20
20
20
20
0
BC

- 11 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. Total Assembly line process
*Connection
4.1. Tool option & ADC Check
1) Press “Power on” key of service remote control.
2) Connect D-SUB cable D-SUB jack for RS232.
3) Check the 'Tool Option' (Refer to the BOM Comments or
Adjustment spec)
4) Check the ‘ADC’ is ok
4.2. Model name & Serial number Down-
load
4.2.1. Model name & Serial number D/L
1) Press "Power on" key of service remote control.
2) Connect RS232 Signal Cable to RS-232 Jack.
3) Write Serial number by use RS-232.
4) Must check the serial number at the Diagnostics of SET UP
menu.
4.2.2. Method & notice
1) Model Name & Serial Number D/L is using of scan equip-
ment.
2) Setting of scan equipment operated by Manufacturing
Technology Group.
3) 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
4) Check the model name Instart menu → Factory name
displayed (ex 24LN4500)
5) Check the Diagnostics (DTV country only) → Buyer model
displayed (ex 24LN4500)
4.3. Function Check
4.3.1. Check display and sound
*Check Input and Signal items. (cf. work instructions)
1) TV
2) AV (CVBS)
3) COMPONENT (480i)
4) HDMI
* Display and Sound check is executed by Remote controller.
→ Caution : Not to push the INSTOP KEY after completion if
the function inspection.
4.4. White balance adjustment
-Equipment
1) Color Analyzer: CA-210 (LED Module : CH 14)
2) Adj. Computer(During auto adj., RS-232C protocol is
needed)
3) Adjust Remocon
RGB_Gains are xed data for each model.
Insert RS-232C Jack which is connected with PC for White
Balance or equivalent device.
* Total Assembly line should be check whether the color
coordinate(x,y) data refer to below table were meet or not.
Color coordinate is differ from panel’s characteristics of color
temperature. Please check panel characteristics about color
temperature.
- Warm Panel
*Note : x,y coordinates are drifted about 0.007 after 30 mins
heat-run. So checking color coordinate within 5-min at
total assembly line, consider x,y coordinates might be
up to 0.007 than x,y target of each color temperature.
▪ White Balance Default value
Color
Temperature
Cool 9,300k °K X=0.290 (±0.04)
Y=0.298 (±0.04)
<Test Signal>
Inner pattern
(204gray,80IRE)
Medium 8,000k °K X=0.300 (±0.04)
Y=0.310 (±0.04)
Warm 6,500k °K X=0.318 (±0.04)
Y=0.334 (±0.04)
Luminance
(cd/m²)
Cool Min : 80 Typ : 110 <Test Signal>
Inner pattern
(204gray,80IRE)
Medium Min : 80 Typ : 110
Warm Min : 80 Typ : 110
Gain Cut
R G B R G B
MT77 22inch LGD
(AH-IPS /
FHD)
Cool 129 163 192 128 128 128
Medium 152 172 192 128 128 128
Warm 188 192 184 128 128 128
24inch CMI
(VA / HD)
Cool 171 172 208 128 128 128
Medium 192 192 188 128 128 128
Warm 192 162 122 128 128 128
29inch Cool 154 172 210 128 128 128
Medium 176 189 192 128 128 128
192 185 141 128 128 128

- 12 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
*Auto-control interface and directions
1) Adjust in the place where the inux of light like oodlight
around is blocked. (Illumination is less than 10ux).
2) Adhere closely the Color Analyzer ( CA210 ) to the module
less than 10cm distance, keep it with the surface of the
Module and Color Analyzer’s Prove vertically.(80~100°).
3) Aging time
- After aging start, keep the power on (no suspension of
power supply) and heat-run over 5 minutes.
- Using ‘no signal’ or ‘full white pattern’ or the others,
check the back light on.
* Auto adjustment Map(RS-232C)
RS-232C COMMAND
[ CMD ID DATA ]
Wb 00 00 White Balance Start
Wb 00 ff White Balance End
** Caution **
Color Temperature : COOL, Medium, Warm.
One of R Gain/G Gain/ B Gain should be kept on 0xC0, and
adjust other two lower than C0.
(when R/G/B Gain are all C0, it is the FULL Dynamic Range
of Module)
*Note : Manual W/B process using adjusts Remote control.
1) After enter Service Mode by pushing "ADJ" key,
2) Enter "White Balance" by pushing "►" key at "White Bal-
ance".
* When doing Adjustment, Please make circumstance as
below.
4.5. Model Name & SW Version & Adjust
check.
* Press the ‘Instart’ key of ADJ remote controller
4.5.1. Model Name& SW Version Check
1) Check ‘Model Name’.
2) Check ‘S/W Version’ (Refer to the IC Ver. in the BOM)
4.5.2. Adjust Check
1) Check ‘Country Group’
2) Check ‘Area Option’
3) Check ‘Tool Option’ (Refer to the BOM Comments)
4) Check ‘EDID[RGB&HDMI]’ is OK.
* After check all, Press the 'EXIT' key of ADJ remote controller
to go out SVC menu.
4.6. Outgoing condition Conguration
* After all function test., press IN-STOP Key by SVC Remote
controller. And make Outgoing Condition
RS-232C COMMAND
[CMD ID DATA]
MIN CENTER
(DEFAULT)
MAX
Cool Mid Warm Cool Mid Warm
R Gain jg Ja jd 00 172 192 192 192
G Gain jh Jb je 00 172 192 192 192
B Gain ji Jc jf 00 192 192 172 192
R Cut 64 64 64 128
G Cut 64 64 64 128
B Cut 64 64 64 128
Color Analyzer
Computer
Pattern Generator
※
※If TV internal patternis used, not needed
Signal Source
Probe
RS-232C
RS-232C
RS-232C
DFT JIG
RGB Cable

- 13 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
TROUBLE SHOOTING
1. No Power
Replace X300
N
Check C500
Voltage Level (19V)
Check Power connector
OK ? Replace Adapter
Y
NY
Check IC501 Output
Voltage Level (3.3V)
Replace IC501 &
Recheck
Y
N
Check X300 Clock
24MHz
Replace IC405 Flash
Memory
Y
Check IC503 Output
Voltage Level (5V)
Replace IC503 &
Recheck
Y
N
Check IC502 Output
Voltage Level (1.15V)
Replace IC502 &
Recheck
N
Y

- 14 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
2. No Picture
Replace Cable
N
Module Back Light On?
Check IC700 & Q700
Replace LED Driver IC or FET
Y
N
N
Check Panel Power 5V (P402 #01)
Check IC503 Output 5V
Replace IC503 &
Recheck
Y
N
Check Panel input Clock
P402 (#10, #11, #22, #23 )
Check IC300
Repair Main B/D
Y
N
Check FFC Cable for Damage or
Open Conductors
Check LED Driver Output
(C706)
Replace T-Con Board or Module
Y
Check IC300
Replace Main SOC
N
Check WLED_ENABLE High?
Y

- 15 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. No Video - Digital TV
Check RF Cable
Y
1. Check RF IC(L200) Power (3.3V)
2. Check IC501 Output voltage(3.3V)
Replace IC501 &
Recheck
Y
N
Check SCL/SDA Line(TU200 #3, #4) Replace TU200 or
IC300(=> Main Scaler)
N

- 16 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. No Video - HDMI
Replace Main Scaler
(IC300)
Check input signal format
Is it supported?
Check JK100 for proper
connection or Damage Replace Connector
Y
N
Check I2C Signal
(JK100) Re Download EDID Data
Y
N
Y
Check HDMI Cable for Damage or
Open Connector
Y

- 17 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
BLOCK DIAGRAM

- 18 - LGE Internal Use Only
Copyright © LG Electronics. Inc. All right reserved.
Only for training and service purposes
EXPLODED VIEW
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.
IMPORTANT SAFETY NOTICE
300 200
120 900
540
910
810
LV1
A2
535
820
800
400
510

USB DOWN STREAM
THE SYMBOL MARK OF THIS SCHEMETIC DIAGRAM INCORPORATES
SPECIAL FEATURES IMPORTANT FOR PROTECTION FROM X-RADIATION.
FIRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS
ESSENTIAL THAT ONLY MANUFACTURES SPECIFIED PARTS BE USED FOR
THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC.
JK103
3AU04S-305-ZC-(LG)
1234
5
D100
RCLAMP0524PA
(OPT)ESD_HDMI_SEMTECH(DEV)
1
8
2
7
3
6
4
5
9
10
JP113
VA111
20V
JP111
JP112
R100
1K
VA108
20V
R121
2.7K
VA102
20V
OPT
D101-*1
IP4283CZ10-TBA
ESD_HDMI_NXP
3
GND_1
2
TMDS_CH1+
4
TMDS_CH2-
1
TMDS_CH1-
5
TMDS_CH2+ 6NC_1
7NC_2
8GND_2
9NC_3
10 NC_4
Q101
MMBT3904(NXP)
E
B
C
R102
10K
VA110
20V
Q100
MMBT3904(NXP)
E
B
C
R110
10K
VA101
5.6V
OPT
+3.3V_ST
VA103
20V
OPT
VA100
20V
OPT
5V_DET_HDMI_1
D100-*1
IP4283CZ10-TBA
ESD_HDMI_NXP
3
GND_1
2
TMDS_CH1+
4
TMDS_CH2-
1
TMDS_CH1-
5
TMDS_CH2+ 6NC_1
7NC_2
8GND_2
9NC_3
10 NC_4
R120
2.7K
VA109
20V
D101
RCLAMP0524PA
(OPT)ESD_HDMI_SEMTECH(DEV)
1
8
2
7
3
6
4
5
9
10
D0-_HDMI1
D2+_HDMI1
D2-_HDMI1
D1-_HDMI1
D1+_HDMI1
D0+_HDMI1
DDC_SDA_1
DDC_SCL_1
CK-_HDMI1
HPD1
CK+_HDMI1
SIDE_USB_DP
SIDE_USB_DM
DDC_SDA_1
DDC_SCL_1
R107
75
1%
R106
75
1%
COMP_DET
VA107
5.6V
OPT
C101
1000pF
50V
R108
470K
OPT
C102
0.1uF
16V
OPT
R118
1K
COMP_Pr+
R113
12K
R117
1K
VA106
5.6V
OPT
VA122
5.6V
OPT
COMP_Pb+
VA105
5.6V
OPT
COMP_R_IN
R105
75
1%
C100
1000pF
50V
R109
470K
OPT
COMP_L_IN
R114
12K
+3.3V
AV_DET
COMP_Y+
P100
Event only
1
2
3
4
5
PM_RXD
PM_TXD
+3.3V_ST
JP120
R153
10K
+3.3V_ST
JP124
VA114
20V
DSUB_HSYNC
2:E18
JP119
DSUB_DET
VA117
5.5V
R144
75
DSUB_B+
DSUB_VSYNC
2:E18
JP122
R145
75
D103
MMBD6100
A2
C
A1
DSUB_R+
JP125
VA119
20V
R148
75
DSUB_G+ JP121
VA120
20V
JK105
SPG09-DB-010
1RED
2GREEN
3BLUE
4GND_1
5DDC_ GND
6RED_ GND
7GREE N_GND
8BLUE _GND
9NC
10 SYN C_GND
11 GND_2
12 DDC _DATA
13 H_SYNC
14 V_SYNC
15 DDC_CLOCK
16 SHILED
Q103
MMBT3904(NXP)
E
B
C
VA121
20V
VA118
5.5V
VA116
5.5V
JP123
JP126
VA115
20V
+5V
PM_TXD
PM_RXD
VA123
20V
OPT VA124
20V
OPT
VA125
20V
OPT
VA126
20V
OPT
JK104
OPT
3 M3_DETECT
4 M4
5 M5_GND
1 M1
6 M6
MGJ63348201
M1
JackShield(for NonCKD)
MGJ63348202
M1-*1
JackShield(for CKD)
JP116 JP128 JP129 JP130
VA113
5.6V
VA104
5.6V
VA112
5.6V
JK100
EAG59023302
14
13
5D1_GND
20
SHIELD
12
11
2D2_GND
19
18
10 CK+
4D1+
1D2+
17
9D0-
8D0_GND
3D2-
16
7D0+
6D1-
15
C103
22uF
6.3V
OPT
IC100
BD2242G
3EN
2GND
4
OC
1VIN
6
VOUT
5
ILIM
R122
4.7K
ZD100
5V
OPT
C105
0.1uF
16V
C104
10uF
10V
R104
14K
R119
10K
USB1_CTL
USB1_OCD
+3.3V
+5V
AR103
100
OPT
AR102
47K
AR101
10K
AR100
10K
AR104
47K
AR105
5.1
AR106
5.1
JK101
PPJ245N2-01
5A [GN/YL]O-SPRING
6A [GN/YL]E-LUG
4A [GN/YL]CONTACT
5B [BL]O-SPRING
7C [RD1]E-LUG-S
5C [RD1]O-SPRING
4C [RD1]CONTACT
5D [WH]O-SPRING
4E [RD2]CONTACT
5E [RD2]O-SPRING
6E [RD2]E-LUG
JP107
JP108
JP109
JP110
D102
MMBD6100
A2
C
A1
+5V
AR107
10K
5V_HDMI_1
5V_HDMI_1
R101
100
R103
100
M1L
JACK INTERFACE
1
2013-07-13
7
<HDMI>
<USB_SIDE>
COMPONENT
<RS232C>
11.10.27
To Improve Ringing issue
LOW capacitance Part apply
<DSUB_RGB>
Jack Shield (HDMI1, HDMI2, RGB)
MAX 1.5A(USB 2.0)
Copyright ⓒ 2015 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only

THE SYMBOL MARK OF THIS SCHEMETIC DIAGRAM INCORPORATES
SPECIAL FEATURES IMPORTANT FOR PROTECTION FROM X-RADIATION.
FIRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS
ESSENTIAL THAT ONLY MANUFACTURES SPECIFIED PARTS BE USED FOR
THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC.
TUNER
C213
0.1uF
16V
C210
22uF
6.3V
+3.3V
L203
UBW2012-121F
+3.3V_TU
C217
0.1uF
16V
C215
22uF
6.3V
R207
1.8K
DIF_N
R208
1.8K
+3.3V_TU
L200 120OHM
C204
18pF
50V
C208
20pF
50V
OPT
TU_SCL
C212
0.1uF
16V
C211
100pF
50V
C207
0.1uF
16V
C209
20pF
50V
OPT TU_SDA
C206
18pF
50V
C214
100uF
16V
105C
OPT
+3.3V_TU
IF_AGC
DIF_P
TU200
TDSS-H701F
5+B1[3.3V]
11 DIF[N]
2NC_2
10 DIF[P]
4SDA
1NC_1
9IF_AGC
8NC_5
3SCL
7NC_4
6NC_3
12
SHIELD
A1 A1
B1
B1
R206 1K
AR200 33
AR201 33
Tuner block 2
M1L
7
2013-07-13
TUNER
60mA
1. should be guarded by ground
2. No via on both of them
3. Signal Width >= 12mils
Signal to Signal Width = 12mils
Ground Width >= 24mils
close to the tuner pin, add,09029
Close to the tuner
KR/US(WO AD)
121118
SS BEAD->SUNLORD BEAD
should be guarded by ground
Copyright ⓒ 2015 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
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4
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