LG M2794D User manual

LCD MONITOR TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : LA97A
MODEL : M2794D M2794D-PMJ
North/Latin America http://aic.lgservice.com
Europe/Africa http://eic.lgservice.com
Asia/Oceania http://biz.lgservice.com
Internal Use Only
P/NO : MFL49414529 (0906-REV00) Printed in Korea

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
- 2 -
CONTENTS
CONTENTS .............................................................................................. 2
PRECAUTIONS .........................................................................................3
SPECIFICATION ........................................................................................6
ADJUSTMENT INSTRUCTION ...............................................................12
TROUBLE SHOOTING ............................................................................15
BLOCK DIAGRAM...................................................................................24
DESCRIPION OF BLOCK DIAGRAM .....................................................25
EXPLODED VIEW .................................................................................. 26
SVC. SHEET ...............................................................................................

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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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

Copyright ©2009 LG Electronics. Inc. All right reserved.
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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

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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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.

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
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SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement .
1. Application Range.
1) This spec sheet is applied all of the LCD TV with LA97A
chassis.
2) Not included spec and each product spec in this spec sheet
apply correspondingly to the following each country standard
and requirement of Buyer
2. Specification
Each part is tested as below without special appointment
1) Temperature : 20±5°C
2) Relative Humidity : 65±10%
3)
Power Voltage : Standard input voltage (100~240V@50/60Hz)
*Standard Voltage of each product 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 20 minutes prior to
the adjustment.
3.Test method
1) Performance :
LGE TV test method followed
2) Demanded other specification
- Safety : L,CSA,IEC specification
- EMC : FCC,ICES,IEC specification
4. General Specification
4.1 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
Recommand 1920x1080 @ 60Hz
Digital Max. 1920x1080 @ 60Hz
Recommand 1920x1080 @ 60Hz
4 Inrush Current Cold Start : 50 A Hot : 120 A
5 Operating Condition Sync (H/V) Video LED Wattage
Power S/W On On mode On/On Active Blue 135W(Max) 1. SO ND: 1/8W non-clipped max.
audio signal
On/On Active Blue 120W(Typ) 2. VIDEO: Color Bar pattern
(Contrast: MAX, Brightness: MAX)
Sleep mode Off/On Off Amber 1W For RGB
On/Off
Power S/W Off Off mode - Off Off 1W
6 MTBF 50,000 HRS with 90% Confidence level
Lamp Life 40,000 Hours (Min)
7 sing Altitude 5,000 m (for Reliability) 3,000m(for FOS)

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Copyright ©2009 LG Electronics. Inc. All right reserved.
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No Item Specification Remarks
1. Receiving System ATSC/NTSC-M
2. Available Channel 1)VHF :02~13
2) HF :14~69
3)DTV :02~69
4)CATV :01~135
5)CADTV :01~135
3. Input Voltage 1)AC 100 ~ 240V 50/60Hz Mark: 110V, 60Hz
4. Market North America
5. Screen Size 27inch FHD
6. Aspect Ratio 16:9
7. LCD Module LM270WF1-TLB1 LGD
8. Operating Environment 1)Temp : 0 ~40 deg
2)Humidity : ~80 %
9. Storage Environment 1)Temp : -20 ~60 deg
2)Humidity : ~85 %
4.2 TV
No Item Content nit Remark
1 Product Width(W) Length(L) Height(H)
Dimension Before Packing 654.1 210 494.6 mm
After Packing 725 535 185 mm
2 Product Only SET 8.92 Kg
With BOX 11.1 Kg
3 Cintaniner 20ft 40ft
Loding Individual or Indi. Wooden Indi. Wooden
Quantity Palletizing 420 330 840 726
4 Stand Assy Type Detachable (Base detachable)
Size (W x D x H) 330.0 x 210.0 x 51.8
Tilt Degree -5~10degree
Tilt force 1.0~3.7kgf
Swivel Degree 358 degree
Swivel Force 0.5 ~2.kgf
5 Appearance General Refer to Standard of LG(55)G1-1020
5. Mechanical specification

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6. Optical characteristic specification
6.1 Chroma &Brightness.
No. Item Specification Remark
Min typ Max
1. Viewing Angle<CR>10> Right/Left 70/70 85/85
p/Down 60/70 75/85
2. Luminance Luminance DVI or RGB
(cd/m2) 320 400 - Stnadard, 6500K
- Full White (100IRE)
Variance(%) 75 Min / Max
3. Contrast Ratio CR 700 1000 Full White/ Full black
4. Color Coordinates White Wx 0.313
[CIE 1931] Wy 0.329
RED Rx Typ 0.661 Typ DVI or RGB
Ry -0.03 0.318 +0.03 - Stnadard, 6500K
Green Gx 0.207 - Full White (100IRE)
Gy 0.668
Blue Bx 0.144
By 0.068
* Optical Test Condition
- Surrounding Brightness Level : dark
- Surrounding Temperature : 25 ± 5°C
- warm-up Time : 30 Min
- Contrast, Brightness : Outgoing condition
- *Incase of Vivid Mode, high level saturation may be occurred.Check gray linearity at standard mode.
* Active area
- Active area of LCD PANEL is in bezel of cabinet.
- Interval between active area and bezel
| A-B|<1.0 mm , | C-D|<1.0 mm
A: Interval between left of active area and bezel
B: Interval between right of active area and bezel
C: Interval between top of active area and bezel
D: Interval between bottom of active area and bezel
C
B
D
A
Active Area
Bezel
No Item Min Typ Max Remark
1. Cool Wx 0.283 0.285 0.287 AV Mode
(9300K) Wy 0.291 0.293 0.295 - RF/ AV1,2,3/ Component/ HDMI
2. Medium Wx 0.293 0.295 0.297 - Vivid
(8000K) Wy 0.203 0.305 0.307 - Cool/ Medium/ Warm: 85IRE
3. Warm Wx 0.311 0.313 0.315 - DTV Signal(16~235): Black Level ; Low
(6500K) Wy 0.327 0.329 0.331 - PC Signal(0~255): Black Level ; High
4. 6500k Wx 0.283 0.313 0.343 PC Mode
Wy 0.299 0.329 0.259 - RGB/ DVI
5. 9300k Wx 0.253 0.283 0.313 - Stnadard
Wy 0.268 0.298 0.328 - 6500K/ 9300K :Full White 100IRE
* se channel 13 of CA-210,because this model is WCG Panel.
6.2 Chroma (PSM :PC Mode-Standard, AV Mode-Vivid)
** The W/B Tolerance is ±0.002 for Adjustment

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Copyright ©2009 LG Electronics. Inc. All right reserved.
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7. SET Optical Feature
7.1 PC Mode (Measurement Condition:Full white/Standard/6500k)-> Measure the black luminance after 30 seconds.
No Item Luminance(cd/m2) C/R Remark
Min Typ Max Min Typ
1 27 inch 320 400 - 700:1 1000:1 DFC 20,000:1
No Item Luminance(cd/m2) C/R(Min) Remark
Min Typ Max RF,AV,COMPONENT,HDMI
1 27 inch 200 270 - 400:1 RF, AV, COMPONENT, HDMI
7.2 AV Mode (Measurement Condition:Full white(100IRE)/Vivid)-> Measure the black luminance after 30 seconds.
No Item Min Typ Max Remark
1 M2794D-PMJ 16000: 1 20000: 1 - For Checking Black Luminance, wait for over 1 minute.
7.3 Dynamic CR
- Dynamic CR Working Condition : Full Black Pattern( All Black, No pattern( MSPG Pattern# 2)) signal in D- sub & DVI
No. Specification Remark
Resolution H-freq(kHz) V-freq(Hz)
1. 720* 480 15.73 59.94 SDTV ,DVD 480I
2. 720* 480 15.73 60.00 SDTV ,DVD 480I
3. 720* 480 31.47 59.94 SDTV 480P
4. 720* 480 31.50 60.00 SDTV 480P
5. 1280* 720 44.96 59.94 HDTV 720P
6. 1280* 720 45.00 60.00 HDTV 720P
7. 1920* 1080 33.72 59.94 HDTV 1080I
8. 1920* 1080 33.75 60.00 HDTV 1080I
9. 1920* 1080 23.0 24.0 HDTV 1080P
10. 1920* 1080 33.75 30 HDTV 1080P
11. 1920* 1080 67.43 59.94 HDTV 1080P
12. 1920* 1080 67.5 60 HDTV 1080P
8. Component Video Input ( , CB/PB, CR/PR)

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9. RGB/DVI
9.1 Input ( PC )
No. Resolution H-freq(kHz) V-freq(Hz) Pixel clock(MHz) Remark
1 720*400 31.468 70.08 28.321
2 640*480 31.469 59.94 25.175 Input 848x480 60Hz, 852x480 60Hz
-> 640x480 60Hz Display
3 640*480 37.5 75 31.5
4 800*600 37.879 60.317 40.0
5 800*600 46.875 75.0 49.5
6 1024*768 48.363 60.0 65.0
7 1024*768 60.123 75.029 78.75
8 1152*864 67.500 75.000 108.0
9 1280*1024 63.981 60.02 108.0
10 1280*1024 79.976 75.035 135.0
11 1680*1050 64.674 59.883 119.0
12 1680*1050 65.290 59.954 1 46.25
13 1600*1200 75.0 60.0 162.0
14 1920*1080 66.587 59.934 138.5
3)Adjustable Data
*: Serial No. .( Input the S/ N at Total Assembly line)
**: week
***: year ex) when year 2006 : input “10”
**** : CHECK S M (deferent along Serial No, week, year)
2) DVI( Digital) EDID - Product ID : 22204
9.2 RGB EDID Data
1) D- S B( Analog) EDID - Product ID : 22203

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10. HDMI1,2
10.1 Input ( DTV: For Video, PC is not Supported)
No. Resolution H-freq(kHz) V-freq(Hz) Pixel clock(MHz) Remark
1 720* 480 31.469 / 31.5 59.94 / 60 23.00/ 23.03 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 / 23 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
10.2 EDID Data
HDMI EDID - Product ID : 22205( HDMI1 and HDMI2 have the Same EDID)
1) HDMI 1

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2) HDMI2
Adjustable Datas( Serial No, week, Year and Check sum) in HDMI EDID are same with RGB/ DVI

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ADJUSTMENT INSTRUCTION
1. Application
1) This spec sheet is applied all of the LCD TV with LA97A
chassis.
2)Not included spec and each product spec in this spec sheet
apply correspondingly to the following each country standard
and requirement of Buyer.
2. Designation
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) Power Adjustment: Free Voltage
3) Magnetic Field Condition: Nil.
4) Input signal nit: Product Specification Standard
5) Reserve after operation: Above 30 Minutes
6) Adjustment equipments: Color Analyzer(CA- 210 or CA- 110),
Pattern Generator (MSPG- 925L or Equivalent ), DDC
Adjustment Jig equipment, SVC remote controller
3. Main PCB check process
# APC - After Manual-Insult, executing APC
# 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.
3.1 ADC Process
3.1.1 PC input ADC
3.1.1.1 Auto RGB Gain/Offset Adjustment
• Convert to PC in Input-source
I2C COMMAND: 0xF4(SELECT_INP T)0x00 0x60 (RGB)
cf 0x10(TV),0x20(AV),0x40(COMPONENT),0x60(RGB),
0x90(HDMI)
• Signal equipment displays
Output Voltage : 700 mVp-p
Impress Resolution XGA (1024 x 768 @ 60Hz)
Model: 60 in Pattern Generator
Pattern: 29 in Pattern Generator (MSPG-925 SERISE)
[gray pattern that left & right is black and center is white
signal (Refer below picture)].
Adjustment pattern (PC )
• Adjust by commanding A TO_COLOR_ADJ ST(0xF1)
0x00 0x02 instruction.
3.1.1.2 Confirmation
• We confirm whether “0xB6(RGB)” address of EEPROM
“0xA2” is “0xAA”or not.
• If “0xB6(RGB)” address of EEPROM “0xB2” isn’t “0xAA”,
we adjust once more
• We can confirm the ADC values from “0xB0~ 0xB5(RGB)”
addresses in a page “0xA2”
*Manual ADC process using Service Remocon. After enter
Service Mode by pushing “INSTART” key, execute “Auto-
RGB” by pushing “ ” key at “Auto-RGB”.
(2) OK
(1) (3)
(4)
filexxx.bin
(6)
filexxx.bin
(5)
(7) ……….OK

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3.2.1COMPONENT input ADC
3.2.1.1Component Gain/Offset Adjustment
• Convert to Component in Input-source
I2C COMMAND :0xF4(SELECT_INP T)0x00 0x40
(COMPONENT)
cf.0x10(TV),0x20(AV),0x40(COMPONENT),
0x60(RGB),0x90(HDMI)
• Signal equipment displays at SD Mode
Impress Resolution: 480i
MODEL :209in Pattern Generator(SD Mode)
PATTERN :08in Pattern Generator(MSPG-925
SERISE)
• Signal equipment displays at HD Mode
Impress Resolution:1080i
MODEL :223in Pattern Generator(HD Mode)
PATTERN :08in Pattern Generator(MSPG-925
SERISE)
Adjustment pattern (COMPONENT )
• Adjust by commanding A TO_COLOR_ADJ ST(0xF1)
0x00 0x02 instruction
3.2.1.2 Confirmation
• We confirm whether “0xC8(1080i)”address of EEPROM
“0xA2” is “0xAA” or not.
• If “0xC8(1080i)” address of EEPROM “0xA2” isn’t
“0xAA”, we adjust once more
• We can confirm the ADC values from “0xC2~(1080i)”
addresses in a page “0xA2”
3.2 Function Check
3.2.1 Check display and sound
• Check Input and Signal items. ( cf. work instructions)
1.TV
2.AV (CVBS/ S-Video)
3.COMPONENT (1080i)
4.RGB (PC: 1680X1050 @60Hz)
5.HDMI
6.PC Audio In and H/P Out
* Display and Sound check is executed by Remote controller.
4. Total Assembly line process
4.1 Adjustment Preparation
• Above 30 minutes H/run in RF no signal
• 15 Pin D-Sub Connector, for IIIC communication not
including VGA signal,is connected to A TO W/B
EQ IPMENT..
* Color Temperature
4.2 Check coordinate of 9300K
•Set Input mode to RGB.
• Set Temperature : 9300K
• Adjust x: 0.285±0.005, y: 0.293±0.005(9300°K )
(Full white MSPG series Pattern 4)
4.3 Check color coordinate of 6500K
• Set Input mode to RGB.
• Set Temperature : 6500K
• Adjust x:0.313±0.005, y:0.329±0.005(6500°K )
(Full white MSPG series Pattern 4)
4.4 DPM operation confirmation (Only Apply for MNT Model)
Check if Power LED Color and Power Consumption operate
as standard.
• Set Input to RGB and connect D-sub cable to set
• Measurement Condition : (100~240V@50/60Hz)
• Confirm DPM operation at the state of screen without Signal
4.5 DDC EDID Write Model Name(M2394D-PMJ)
• Connect D- sub Signal Cable to D-Sub Jack.
• Connect DVI Signal Cable to DVI Jack.
• Connect HDMI1,2 Signal Cable to HDMI1,2 Jack.
• Write EDID DATA to EEPROM(24C02) by using DDC2B
protocol.
• Check whether written EDID data is correct or not.
(refer to Product spec).
4.6 HDCP (High-Bandwidth Digital Contents Protection)SETTING
• Connect D-sub Signal Cable to D-Sub Jack
• Input HDCP key with HDCP-key-in-program
• HDCP Key value is stored on EEPROM(AT24C512) which
is 80~A1 addresses of 0xA0~0xA2 page
• AC off/on and on HDCP button of MSPG925 and confirm
whether picture is displayed or not of using MSPG925
• HDCP Key value is different among the sets.
4.7 Outgoing condition Configuration
• After all function test., press IN-STOP Key by SVC Remote
controller. And Make Ship Condition.
• When pressing IN-STOP key by SVC remocon, Red LED
are blinked alternatively. And then Automatically turn off.
(Must not AC power OFF during blinking)
4.8 Internal pressure
• Confirm whether is normal or not when between power
board's ac block and GND is impacked on 1.5kV(dc) or
2.2kV(dc) for one second
Cool 9,300 K X=0.285
Y=0.293
<Test Signal>
Inner pattern
(216 Gray level, 8 IRE)
MSPG Series Pattern 78
Medium 8,000 K X=0.295
Y=0.305 (216 Gray level, 8 IRE) MSPG Series Pattern 78
Warm 6, 00 K X=0.313
Y=0.329 (216 Gray level, 8 IRE) MSPG Series Pattern 78
o
o
o

- 15 -
Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
5. Adjustment Command
5.1 Adjustment Commands(LEMGTH=84)
5.2 EEPROM DATA READ
5.2.1 Signal Table
5.2.2 Command Set
*use: To read the appointment Address of E
5.3 E2PROM Data Write
5.3.1 Signal Table
LEN : 84h + Byte
CMD : 8Eh
ADH : E2PROM Slave Address (A0, A2, A4, A8), Not 00h
(Reserved by Buffer to E2PROM )
ADL : E2PROM Sub Address ( 00~ FF)
Data : Write data
5.3.2 Command Set
- use
• EDID write : 16-byte by 16-byte, 8 order (128-byte)
write(TO “00 – 7F” of “EEPROM Page A4”)
• FOS Default write : 16-mode data
(HFh,HFl,VF,STD,HP,VP,Clk,ClkPh,PhFine) write
• Random Data write : write the appointment Address of
E2PROM
5.4 VRAM Read
• Send CMD(70h) to read Video RAM value from MICOM
And save its value to 128-Bytes Buffer(Common Buffer
for the use of EDID)
• Delay 500ms ( Time to Wait and Read Video RAM from
MICOM)
• Be transmitted the contents of MICOM’s 128-bytes
Buffer to PC.
(128th Data is the CheckSum of 127-bytes data : That’s
OK if the value of adding 128-bytes Data is Zero)
No. Adjustment Contents CMD ADR VAL Description
1 FACTORY ON E0 00 00 Factory mode on
2 FACTORY OFF E2 00 00 Factory mode off
3 EEPROM ALL INIT. E4 00 00 EEPROM All clear
4 EEPROM Read E7 00 00 EEPROM Read
5 EEPROM Write E8 00 Data EEPROM Write by some values
6
COLOR SAVE (R/G/B cutoff)
Drive, Contrast, Bright) EB 00 Save
7 20 00 00~100
8 V POSITION 30 00 00~100
9 CLOCK 90 00 00~100
10 PHASE 92 00 00~100
They have different range
mode, FOS Adjustment
11 R DRIVE 16 00 00~FF
12 G DRIVE 18 00 00~FF
13 DRIVE 1A 00 00~FF
Drive adjustment
14 R C TOFF 80 00 00~7F
15 G C TOFF 82 00 00~7F
16 B C TOFF 84 00 00~7F
Offset adjustment
17 BRIGHT 10 00 00~3F
19 CONTRAST 12 00 00~64
Bright adjustment
Luminance adjustment
20 A TO_COLOR_
ADJ ST F1 00 02 Auto COLOR Adjustment
21 CHANGE_COLOR_TEMP 00 0,1,2,3
0: COOL
1: NORMAL
2: WARM
3: SER
22 FACTORY_DEFA LT F3 00 00
Factory mode off
& II_SW is “1”
& Input change to “ TV”
23 A TO_INP TCHANGE 00
0 : TV
1 : AV1
2 : AV2
3 : Component
4 : RGB
5 : DVI
6 : HDMI
00 Color
F4 0,1,2,4
POSITION H
B
F2
----------------------------------------------------------------------
128 Bytes
STOP
A A D1 6F
STOP
START
A
A
A
Dn
A A A 50 6E 03 C D ADH84 START A A ADL A CS
No. contents CMD A DH ADL Details
1 EEPROM READ E7 A0 0 0-Page 0~7F Read
2 80 0-Page 80~FF Read
3 A2 0 1-Page 0~7F Read
4 80 1-Page 80~FF Read
5 A4 0 2-Page 0~7F Read
6 80 2-Page 80~FF Read
7 A6 0 3-Page 0~7F Read
8 80 3-Page 80~FF Read
Adjustment
STOP
AAA AA 50 6E 03 C D ADH84+n START ADL A
CS
A
AData_1 A . . . Data_n A
No. Adjustment contents CMD(hex) LEN Details
1 EEPROM WRITE E8 94 16-Byte Write
2 84+n n-byte Write
STOP
AAAA A 506E 03 70 0084 START AA 00 A CS
ACSA Data1 6F START . . . Data128 STOP
NA

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
- 16 -
TROUBLESHOOTING
1. Power- Up Boot Fail Trouble Shooting
Check P700 All
Voltage Level (5V, 15V)
Check Pow er con nector
OK ? Replace Po wer board
Y
N
Check IC705 #2 Pin
Voltage Level 3.3V
Replace IC 705 &
Recheck
Y
N
Check X101 Clock
12MHz Replace X 101
Y
N
Replace IC 106 Flash
Memory
Check Q702 Outp ut
Voltage Level (5V) Replace Q702
N
Y
Wave form of X101
N
Wave form of X101

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
- 17 -
2. No OSD Trouble Shooting
Check P30 2
#8(TXEC+) , #9(TXEC-) ,
#20(TXOC+) , #21(TXOC-)
IC101 has problem
Check L VDS Cable for damage or ope n
con ductors .
Check L CD Module
Control board
(Refer to Module CAS)
Y
N
Y
Replace Ca ble
N
Y
1. Check Po wer Board , 15V
2. Check Q702 Output voltage(5V)
3. Check P302(#1, 2, 3) 5V
1. Replace Power Board
2. Replace Q702
N
Check P70 0(#9)
INV_ON high
Check GPIO Path
(Refer to Appe ndix 1 .)
N
Y

Check RF Ca ble
Check T P Clock, Data, Sync
R440, R441, R442 Maybe Tun er(T 400) has problems
Check IC10 1 LVDS output
#8(TXEC+) , #9(TXEC-) ,
#20(TXOC+) , #21(TXOC-)
Y
N
Check Tu ner 5V Po wer &
Q707 5V Replace Q7 07
Y
N
Y
Replace IC101 has problems
N
Y
Check L D400 color Bad Tun er. Replace Tuner.
None Yello w ->-> none
Check Demod ulator Input Clock
X400 (25MHz) Replace X400
N
Y
Check L CD Module
Control board
Refer to Mo dule CAS
Wave form of X400
Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
- 18 -
3. Digital TV Video Trouble Shooting
->
Wave form of X400

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
- 19 -
4. Component Video Trouble Shooting
Check inpu t signal for mat
Is it supported?
Check signal
C124, C126, C129
Check R10 7, R109, R112,
C124, C126, C129
Y
N
Check J K602 Replace JK602 or Che ck Divice
Y
N
Y
IC101 has problem
Y
Check Compo nent Cab le
Wave form of C124 Wave form of C126 Wave form of C129
Wave form of Comp Y Wave form of Comp Pb Wave form of Comp Pr

Copyright ©2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal se Only
- 20 -
5. RGB Video Trouble Shooting
Check inpu t signal format
Is it supported?
Check signal , Hsync, Vsync
(R673, R674) Replace R6 73, R674
Check signal RGB
(R119, R104, R105
C121,C122,C119)
Y
N
Check JK607 Replace JK607
Y
N
Y
Replace R119, R104, R105,
C121,C122,C119
N
IC101 has problem
Y
Check RGB Cable connector
for damage
Y
Wave form of R673(Vsync) Wave form of R673(Vsync)
Wave form of R104/C121
Wave form of R105/C122 Wave form of R119/C119