LG M2550D User manual

LED LCD TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : LD11C
MODEL : M2550D M2550D-PSN
North/Latin A erica http://aic.lgservice.co
Europe/Africa http://eic.lgservice.co
Asia/Oceania http://biz.lgservice.co
Internal Use Only
P/NO : MFL63642153(1108-REV00) Printed in Korea

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CONTENTS
CONTENTS .............................................................................................. 2
PRECAUTIONS .........................................................................................3
SPECIFICATION ........................................................................................6
ADJUSTMENT INSTRUCTION................................................................11
TROUBLE SHOOTING ............................................................................15
BLOCK DIAGRAM...................................................................................20
EXPLODED VIEW .................................................................................. 21
SCHEMATIC CIRCUIT DIAGRAM...............................................................

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SAFET 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. se 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 1MΩ and 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
To Instrument's
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
COND IT 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 SAFET NOTICE
0.15uF
Ω

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CA TION: 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. nless 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.
nless 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 s ecified 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. se only a grounded-tip soldering iron to solder or unsolder ES
devices.
4. se 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. se a grounded-tip, low-wattage soldering iron and appropriate
tip size and shape that will maintain tip temperature within the
range or 500ºF to 600ºF.
2. se 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. se a mall wire-
bristle (0.5 inch, or 1.25cm) brush with a metal handle.
Do not use freon-propelled spray-on cleaners.
5. se the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.
(500ºF to 600ºF)
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.
CA TION: Work quickly to avoid overheating the circuit
board printed foil.
6. se the following soldering technique.
a. Allow the soldering iron tip to reach a normal temperature
(500ºF to 600ºF)
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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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.
Re lacement
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 " " shape the end of each of three leads remaining
on the circuit board.
3. Bend into a " " shape the replacement transistor leads.
4. Connect the replacement transistor leads to the corresponding
leads extending from the circuit board and crimp the " " 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. ( se 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 " " 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
se 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
NOTE : Specifications and others are subject to change without notice for improvement .
1. Application Range.
This spec sheet is applied all of the LED LCD TV used LD11C
chassis.
2. Specification
Each part is tested as below without special appointment
2.1 Temperature : 25 °C ± 5 °C (77 °F ± 9 °F),
CST : 40 °C ± 5° C
2.2 Relative Humidity : 65 % ±10 %
2.3 Power Voltage : Standard input voltage
(100 V - 240 V ~, 50 / 60 Hz)
• Standard Voltage of each products is marked by models
2.4 Specification and performance of each parts are followed
each drawing and specification by part number in
accordance with BOM .
2.5 The receiver must be operated for about 5 minutes prior to
the adjustment.
3. Module Specification
3.1. General Features
Model Market Brand
M2550D Brazil LG
No Item Specification nit Remark
1 Panel Size 634.4mm(25 inches)
2 Panel Type TN
3 Operating Mode Normally White
4 Backlight nit White LED
5 Max Resolution 1920 x 1080
6 Pixel Pitch 0.288(H) x 0.288(V)
7 Interface LVDS 2Port
8 Color depth 16.7M (6bit+A FRC)
LGD/ LM250WF2-TLA1 ( P/ N : EAJ61528801)
No. Item Specification Min. Typ. Max. Remark
1 Viewing Angle[CR>10] Right/Left 70/70 85/85 -
p/Down 60/70 75/85
2 Luminance Luminance (cd/m2) 200 250 -
Variation(%) 75 %
3 Contrst Ratio CR 700 1000
4 Color Coordinates RED Rx- 0.646 -
Ry- 0.331 -
Green Gx- 0.294 -
Gy- 0.635 -
Blue Bx- 0.150 -
By- 0.067 -
White Wx- 0.313 -
Wy- 0.329 -
3.2. Optical Spec.

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4. General specification
4.1 TV
4.2 RGB(PC)
No Item Specification Remarks
1 Supported Sync. Type Separate Sync., Digital
2 Operating Frequency Analog Horizontal 30 ~ 83kHz
Vertical 56 ~ 75 Hz
Digital Horizontal 30 ~ 83kHz
Vertical 56 ~ 75 Hz
3 Resolution Analog Max. 1920x1080 @ 60Hz
Recommend 1920x1080 @ 60Hz
Digital Max. 1920x1080 @ 60Hz
Recommend 1920x1080 @ 60Hz
4 Operating Environment Temp : 10°C ~ 35°C
Humidity : 20 % ~ 80 %
5 Storage Environment Temp : -10°C~60°C non condensing
Humidity : 5 % ~ 90 % non condensing
No Item Specification Remarks
1 Market Brazil
2 Receiving System 1)SBTVD / PAL-M / PAL-N
3 Available Channel 1) VHF : 02~13 2) HF : 14~69
3) DTV : 07-69 4) CATV : 01~135
4 Component Input (1EA) Y/Cb/Cr , Y/Pb/Pr
5 RGB Input RGB-PC Analog (D-S B 15Pin)
6 HDMI Input (2EA) HDMI Rear / HDMI version 1.3/ support PC
7 Audio Input (2EA) RGB Audio
Component L/R Input
8 SPDIF out (1EA) SPDIF out
9 Earphone out (1EA) Antenna, Component, RGB, HDMI
10 SB (1EA) Picture, Music, Movie, SVC Software pdate + Picture + Music + Movie
11 RS-232C (1EA) Commercial Mode
12 Local Key (Touch) INP T, MEN , ENTER,
F VOL G ,
E CH D , POWER ON/OFF

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No Item Min Typ Max Remark
1. C50:Cool White Balance,X axis 0.255 0.285 0.315 DQA :±0.03 Measurement Condition
(9300k) White Balance,Y axis 0.263 0.293 0.323 DQA :±0.03 : After 30min aging
2. 0: Medium White Balance,X axis 0.263 0.295 0.325 DQA :±0.03
(8000k) White Balance,Y axis 0.275 0.305 0.335 DQA :±0.03
3. W50: Warm White Balance,X axis 0.283 0.313 0.343 DQA :±0.03
(6500k) White Balance,Y axis 0.299 0.329 0.359 DQA :±0.03
5. Optical Specification of SET
5.1 Color coordinate
** The W/B Tolerance is ±0.01 for Adjustment, but for DQA ± 0.03
5.2 Luminance and Contrast Ratio
- PC Mode(RGB)
No. Item Luminance(cd/m2) C/R Remark
Min Typ Max Min Typ
Measurement Condition
: After 30min aging
1 M23/2550D 180 200 - 800 1000
- AV Mode(RF, Component, HDMI)
No. Item Luminance(cd/m2) C/R(min) Remark
Min Typ Max RF, AV, COMPONENT, HDMI
1 M23/2550D 180 200 - 800 Measurement Condition
: After 30min aging
- DFC(RGB)
No. Item Luminance(cd/m2) Remark
Min Typ Max
1 M23/2550D 4M:1 5M:1 Measurement Condition(after 30min aging)
- Picture setting : Outgoing condition
- Should be measured at least after 30 seconds on DFC mode.
- Input signal : 100IRE White pattern (Pattern #4 :MSPG series)
- Full Black pattern (Pattern #2 : MSPG series)
- Equipment : CA-210 (Ch. 14 WLED) or equivalent device.

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7. Timing
7.1 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 60.023 75.029 78.750
8. 1152*864 67.500 75.000 108.000
9. 1280*720 45.000 60.000 74.250
10. 1280*800 49.702 59.810 83.500
11. 1280*1024 63.981 60.020 108.000
12. 1280*1024 79.976 75.025 135.000
13. 1400*1050 65.317 59.978 121.750
14. 1440*900 55.935 59.887 106.500
15. 1600*900 60.000 60.000 108.000
16. 1680*1050 64.674 59.883 119.000
17. 1680*1050 65.290 59.954 146.250
18. 1920*1080 67.500 60.000 148.500
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
7.2 HDMI (DTV)
6. Power Consumption
1 Operating Condition Sync (H/V) Video LED Wattage Condition
Power S/W On On Typ. On/On Active On 40 W * Energy Saving Spec
mode Max. On/On Active On 50 W - Off : 100%
Sleep mode. On/On Active ON(20%) 1 W - Minimum : Below 90%
- Medium : Below 80%
Power S/W Off Off mode - Off Off 0.5W - Maximum : Below 70%
* LED(SET) operation : The brightness of the power indicator will be reduced by 20% when the TV is in power-
saving mode.

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No. Specification Remark
Resolution H-freq(kHz) V-freq(Hz) Pixel clock( MHz)
1. 720* 480 15.73 59.94 13.500 SDTV, DVD 480I( 525I)
2. 720* 480 15.75 60.00 13.514 SDTV, DVD 480I( 525I)
3. 720* 576 15.625 50.00 13.500 SDTV, DVD 576I( 625I) 50Hz
4. 720* 480 31.47 59.94 27.000 SDTV 480P
5. 720* 480 31.50 60.00 27.027 SDTV 480P
6. 720* 576 31.25 50.00 27.000 SDTV 576P 50Hz
7. 1280* 720 44.96 59.94 74.176 HDTV 720P
8. 1280* 720 45.00 60.00 74.250 HDTV 720P
9. 1280* 720 37.50 50.00 74.25 HDTV 720P 50Hz
10. 1920* 1080 33.72 59.94 74.176 HDTV 1080I
11. 1920* 1080 33.75 60.00 74.250 HDTV 1080I
12. 1920* 1080 28.125 50.00 74.250 HDTV 1080I 50Hz,
13. 1920* 1080 56.25 50 148.5 HDTV 1080P
14. 1920* 1080 67.432 59.94 148.350 HDTV 1080P
15. 1920* 1080 67.5 60.00 148.5 HDTV 1080P
7.3 Component

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1. Application
This document is applied to LD11C chassis LCD LED TV
which is manufactured in TV (or Monitor) Factory or is
produced on the basis of this data.
2. Designation
2.1 The adjustment is according to the order which is
designated and which must be followed, according to the
plan which can be changed only on agreeing.
2.2. Power Adjustment: Free Voltage
2.3. Magnetic Field Condition: Nil.
2.4. Input signal nit: Product Specification Standard
2.5. Reserve after operation: Above 5 Minutes (Heat Run)
Temperature : at 25°C ± 5°C
Relative humidity : 65 ±10%
Input voltage : 220V, 60Hz
2.6. Adjustment equipment: Color Analyzer (CA-210 or CA-
110), Pattern Generator (MSPG-925L or Equivalent),
DDC Adjustment Jig equipment, SVC remote controller
2.7. Don’t push The “IN STOP KE ” after completing the
function inspection.
3. Tool Option
4. Main PCB check process
• APC - After Manual-Insult, executing APC
4.1 Download
1) Execute ISP program "Mstar ISP tility" and then click
"Config" 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.
4) Click "Read" tab, and then load download file(XXXX.bin) by
clicking "Read"
5) Click "Auto" tab and set as below
6) Click "Run".
7) After downloading, check "OK" message.
ADJUSTMENT INSTRUCTION
(1) (3)
(2) OK
Please Check the Speed :
To use speed between
from 200KHz to 400KHz
(4)
filexxx.bin
filexxx.bin
(7)
(5)
(8) ……….OK
(6)

4.2 DOWNLOAD USB
1) Make New folder named “LG_DTV” and put ISP file(*.epk)
in the folder.
2) Put the SB Stick to the SB socket
3) Automatically detecting update file in SB Stick
If your downloaded program version in SB Stick is Low, it
didn’t work.
But your downloaded version is High, SB data is
automatically detecting
4) Show the message “Copying files from memory”
5) pdating is staring.
6) pdating Completed, The TV will restart automatically.
7) If your TV is turned on, check your updated version and
Tool option. (explain the Tool option, next stage)
* If downloading version is more high than your TV have, TV
can lost all channel data. In this case, you have to channel
recover. if all channel data is cleared, you didn’t have a
DTV/ATV test on production line.
* After downloading, have to adjust TOOL OPTION again.
1) Push "ADJ" key in service remote controller
2) Select "1.Tool Option" and Push “OK” button
3) Punch in the number. (Each model has their number.)
4) Completed selecting Tool option
4.3 ADC Process
1) Press the “ADJ” KEY on R/C and enter EZ ADJ ST.
2) Enter ADC Calibration mode by pushing “G”key at “6. ADC
Calibration”.
3) Push the “Start” button.
4) ADC Calibration External is executed automatically.
5) Press “EXIT”key on R/C.
Adjust Sequence
*aa 00 00 [Enter Adjust Mode]
*xb 00 40 [Component1 Input (480i)]
*ad 00 10 [Adjust 480i Comp1]
*xb 00 60 [RGB Input (1024*768)]
*ad 00 10 [Adjust 1024*768 RGB]
*aa 00 90 End Adjust mode
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NO. Item CMD 1 CMD 2 Data 0
Enter Adjust ‘Mode In’ A A 0 0 When transfer the ‘Mode In’
Adjust MODE Carry the command.
ADC adjust ADC Adjust A D 1 0 Automatically adjustment
(The use of a internal pattern)

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4.4 EDID
4.4.1 EDID download
1) Press “Power only” key of service remote control.
2) Press the ADJ KEY on R/C and enter EZ ADJ ST
3) Select “8.EDID D/L” by using
E / D (CH +/-) and press ENTER.
4) Select “Start” and press navigation key(G).
5) EDID download is executed automatically.
6) Press EXIT key on R/C.4.4.1 RGB EDID Data
4.4.2 RGB EDID Data
- M2550D(Product ID : 22664)
4.4.3 HDMI EDID Data
- M2550D(Product ID : 22666)
* Edid data and Model option download (RS232)
-->Caution:
- Never connect HDMI & D-sub Cable when the user
downloading .
- Download HDMI1, HDMI2 separately because HDMI1 is
different from HDMI2..
4.5 Function Check
4.5.1 Check display and sound
* Check Input and Signal items. (cf. work instructions)
1) TV
2) COMPONENT (480i)
3) RGB
4) HDMI1/2
5) PC Audio In
* Display and Sound check is executed by Remote control
5. Total Assembly line process
5.1 Tool option & CI+ & ADC check
1) Press “Power on”key of service remote control.
2) Connect RS232 Signal Cable to RS-232 Jack.
3) Check the 'Tool Option' (Refer to the BOM Comments or
Adjustment spec)
4) Check the ‘ADC’ is ok.00
5.2 Model name & Serial number Download
5.2.1 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 P
menu. (Refer to below).
5.2.2 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.
1) Press the ‘Instart’ key of ADJ remote controller.
2) Go to the menu ‘5.Model Number D/L’ like below photo.
3) Input the Factory model name(ex M2350D-PSN) or Serial
number like photo.
4) Check the model name Instart menu --> Factory name
displayed (ex M2350D-PSN
5) Check the Diagnostics (DTV country only) --> Buyer model
displayed (ex M2350D)
NO. Item CMD 1 CMD 2 Data 0
Enter Download A A 0 0 When transfer the ‘Mode In’
download MODE ‘Mode In’ Carry the command.
EDID data and Download A E 00 10 Automatically download
Model option (The use of a internal pattern)

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Copyright ©2011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
5.3 White balance adjustment
RGB_Gains are fixed 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.
* 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.
* Note : Manual W/B process using adjusts Remote control.
1) After enter Service Mode by pushing “ADJ” key,
2) Enter “White Balance” by pushing “G”key at “6. White
Balance”.
* When doing Adjustment, Please make circumstance as
below.
5.4 DPM operating check
* Measurement Condition: 100~240V@ 50/60Hz
1) Set Input to RGB-PC and connect D-sub cable to set - RGB
Mode
Set Input to HDMI1/2(with Input Label set to PC) and
connect HDMI1/2 cable to set - HDMI Mode
2) Cut off H sync or V sync of signal.
3) Check DPM operation refer to the below table.
* LED(SET) operation : The brightness of the power indicator
will be reduced by 20% when the TV is in power-saving mode.
5.5 Model Name & SW Version & Adjust check.
* Press the ‘Instart’ key of ADJ remote controller
5.5.1 Model Name& SW Version Check
1) Check ‘Model Name’.
2) Check ‘S/W Version’ (Refer to the IC Ver. in the BOM)
5.5.2 Adjust Check
1) Check ‘Country Group’
2) Check ‘Tool Option’ (Refer to the BOM Comments)
3) Check ‘Adjust ADC[Comp&RGB]’ is OK.
4) Check ‘EDID[RGB&HDMI1/2]’ is OK.
* After check all, Press the 'EXIT' key of ADJ remote controller
to go out SVC menu.

Copyright ©2011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
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TROUBLESHOOTING
1. Power- Up Boot Fail Trouble Shooting

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Only for training and service purposes
LGE Internal se Only
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2. No Picture Trouble Shooting

Copyright ©2011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
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4. Analog TV Video Trouble Shooting
3. Digital TV Video Trouble Shooting

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Only for training and service purposes
LGE Internal se Only
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5. Component Video Trouble Shooting
6. RGB Video Trouble Shooting

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Copyright ©2011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
7. HDMI Video Trouble Shooting
8. All Source Audio Trouble Shooting

Copyright ©2011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
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BLOCK DIAGRAM