LG LD84J M237WD, M237WD-PMJ LCD monitor TV SERVICE MANUAL

North/Latin America

Europe/Africa

Asia/Oceania

Internal Use Only

http://aic.lgservice.com

http://eic.lgservice.com

http://biz.lgservice.com

LCD MONITOR TV

SERVICE MANUAL

CHASSIS : LD84J

MODEL : M237WD

M237WD-PMJ

CAUTION

BEFORE SERVICING THE CHASSIS,

READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

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 ...............................................................................................

Only for training and service purposes

- 2 LGE Internal Use Only

SAFETY PRECAUTIONS

IMPORTANT SAFETY NOTICE

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 1M

Ω and 5.2M

Ω

.

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

AC Volt-meter

To Instrument’s exposed

METALLIC PARTS

0.15uF

1.5 Kohm/10W

Good Earth Ground such as WATER PIPE,

CONDUIT etc.

When 25A is impressed between Earth and 2nd Ground for 1 second, Resistance must be less than 0.1

Ω

*Base on Adjustment standard



SERVICING PRECAUTIONS

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.

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.)

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

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 500ºF to 600ºF.

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 wirebristle (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.

(500ºF to 600ºF) b. Heat the component lead until the solder melts.

c. Quickly draw the melted solder with an anti-static, suctiontype 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

(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.



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


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


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.

- 5 -

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.

LGE Internal Use Only


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 LD84J 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

3.Test method

3.1 Performance :

LGE TV test method followed

3.2 Demanded other specification

- Safety : UL,CSA,IEC specification

- EMC : FCC,ICES,IEC specification

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

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 20 minutes prior to the adjustment.

4. General Specification

4.1 PC

No Item

1 Supported Sync. Type

2 Operating Frequency

3 Resolution

4 Inrush Current

5 Operating Condition

Power S/W On On mode

Specification

Separate Sync., Digital

Analog

Digital

Horizontal

Vertical

Horizontal

Vertical

30 ~ 83kHz

56 ~ 75 Hz

30 ~ 83kHz

56 ~ 75 Hz

Analog

Digital

Max.

1920x1080 @ 60Hz

Recommand 1920x1080 @ 60Hz

Max.

1920x1080 @ 60Hz

Recommand 1920x1080 @ 60Hz

Cold Start : 50 A Hot : 120 A

Sync (H/V) Video LED

On/On Active Blue

Wattage

55W (Max)

Remarks

Power S/W Off

6 MTBF

7 Using Altitude

Sleep mode

Off mode

Off/On

On/Off

-

Off Amber 1W

Off Off

50,000 HRS with 90% Confidence level

5,000 m (for Reliability) 3,000m(for FOS)

1W

Lamp Life 40,000 Hours (Min)



4.2 TV

No

1.

2.

Item

Receiving System

Available Channel

Specification

ATSC/64 &256 QAM/NTSC-M

1)VHF :02~13

2)UHF :14~69

3)DTV :02-69

4)CATV :01~135

5)CADTV :01~135

1)AC 100 ~ 240V 50/60Hz 3.

4.

5.

6.

7.

8.

Input Voltage

9.

Screen Size

Aspect Ratio

LCD Module

Operating Environment

Storage Environment

23 inch Wide(23.00 inch)

16:9

LM230WF1-TLA1(1920 x1080)

1)Temp :0 ~40 deg

2)Humidity :~80 %

1)Temp :-20 ~60 deg

2)Humidity :0 ~90 %

5. Optical characteristic specification

5.1 Chroma &Brightness.

No.

Item

1.

Viewing Angle<CR>10>

2.

Luminance

Right/Left

Up/Down

Luminance

(cd/m2)

Specification

Min

70/70

60/70

25 0

USA ONLY

Remarks

Non-Glare,Wide,LPL TN typ

85/85

75/85

300

Max

Remark

DVI or RGB

- Stnadard, 6500K

- Full White (100IRE)

3.

Contrast Ratio

Variance(%)

CR

75

600 1000

4.

Color Coordinates

[CIE 1931]

White

RED

Wx

Wy

Rx

Ry

Typ

0.313

0.329

0.644

0.336

Typ

-0.03

Green Gx

Gy

0.295

0.614

Blue Bx 0.146

By 0.072

* 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.

Full White/ Full black

DVI or RGB

- Stnadard, 6500K

- Full White (100IRE)

C

* 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

A

D

B

Active Area

Bezel



5.2 Chroma (PSM :PC Mode-Standard, AV Mode-Vivid)

** The W/B Tolerance is ±0.002 for Adjustment, but for DQA ±0.015

No

1. Cool

Item

(9300K)

2. Medium

(8000K)

3. Warm

(6500K)

4. 6500k

5. 9300k

Wx

Wy

Wx

Wy

Wx

Wy

Wx

Wy

Wx

Wy

Min Typ Max

0.283 0.285 0.287

0.291

0.293

0.203

0.311

0.327

0.283

0.299

0.253

0.268

0.293

0.295

0.305

0.313

0.329

0.313

0.329

0.283

0.298

0.295

0.297

0.307

0.315

0.331

0.343

0.359

0.313

0.328

- RGB/ DVI

Remark

- RF/ AV1,2,3/ Component/ HDMI

- Cool/ Medium/ Warm: 85IRE

- 6500K/ 9300K :Full White 100IRE

*The spec range of Color coordinates is same with the one of module,because this model does not adjust white balance.

6. SET Optical Feature

6.1 PC Mode (Measurement Condition:Full white/Standard/6500k)-> Measure the black luminance after 30 seconds.

No

1

Item Luminance(cd/m 2 ) C/R

23 inch

Min Typ

250 300

Max Min Typ

600:1 1000:1

Remark

DFC 30,000:1

6.2 AV Mode (Measurement Condition:Full white(100IRE)/Vivid)-> Measure the black luminance after 30 seconds.

No Item Luminance(cd/m

2

) C/R(Min)

Min Typ

170 220 400:1

Remark

6.3 Dynamic CR

- Dynamic CR Working Condition : Full Black Pattern( All Black, No pattern( MSPG Pattern# 2)) signal in D- sub & DVI

No

1

Item Min Typ

M237WD-PMJ 24000: 1 30000: 1 For Checking Black Luminance, wait for over 1 minute.

7. Mechanical specification

No

1 Product

Dimension

Unit Remark

2

3

4

5

Product

Cintaniner

Loding

Quantity

Stand Assy

Appearance

Item

Before Packing

After Packing

Only SET

With BOX

Width(W)

560.8

651

Content

Length(L)

5.6

7.4

193.2

456

Height(H)

427

161

Individual or

Palletizing

Type

20ft 40ft

Indi. Wooden Indi. Wooden

630 520

Detachable

1260 1144

Size (W x D x H) 271.2 x 193.2 x 108.4

Tilt Degree -5~15degree

Tilt force

General

0.8~3.5kgf

Refer to Standard of LG(56)G1-1020 mm mm

Kg

Kg



8. Component Video Input (Y, P

B

, P

R

)

Specification

No.

Remark

1.

2.

3.

4.

5.

6.

7.

8.

720* 480

720* 480

720* 480

720* 480

1280* 720

1280* 720

1920* 1080

1920* 1080

15.73

15.73

31.47

31.50

44.96

45.00

33.72

33.75

23.0

33.75

67.43

67.5

59.94

60.00

59.94

60.00

59.94

60.00

59.94

60.00

24.0

30

59.94

60

10. RGB/DVI

10.1 Input ( PC )

No. Resolution H-freq(kHz) V-freq(Hz) clock(MHz)

1 720*400 31.468

70.08

28.321

2 640*480 31.469

59.94

25.175

SDTV ,DVD 480I

SDTV ,DVD 480I

SDTV 480P

SDTV 480P

HDTV 720P

HDTV 720P

HDTV 1080I

HDTV 1080I

Remark

Input 848x480 60Hz, 852x480 60Hz

-> 640x480 60Hz Display

3 640*480

4 800*600

37.5

37.879

75

60.317

31.5

40.0

5 800*600

6 1024*768

46.875

48.363

75.0

60.0

49.5

65.0

7 1024*768 60.123

75.029

78.75

8 1152* 67.500 75.000 108.0

63.981 60.02 108.0

65.290 46.25

10.3 RGB EDID Data

- Analog EDID_Product ID :22251



- DVI(Digital)EDID_Product ID :22252

- Adjustable Data :

*: Serial No. .( Input the S/ N at Total Assembly line)

**: week

***: year ex) when year 2006 : input “10”

**** : CHECK SUM (deferent along Serial No, week, year)

12. HDMI1,2

12.1 Input ( DTV: For Video, PC is not Supported)

No. Resolution H-freq(kHz) V-freq(Hz) clock(MHz)

1 720* 480 31.469 / 31.5 59.94 / 60 23.00/ 23.03 SDTV 480P

2 720* 576

3 1280* 720

4 1280* 720

5 1920* 1080

31.25

37.500

44.96 / 45

33.72 / 33.75

50

50

59.94 / 60

59.94 / 60

54

74.25

74.17/ 74.25

74.17/ 74.25

SDTV 576P

HDTV 720P

HDTV 720P

HDTV 1080I

6 1920* 1080

7 1920* 1080

8 1920* 1080

10 1920* 1080

28.125

26.97 / 23

33.716 / 33.75

56.250

67.43 / 67.5

50.00

23.97 / 24

29.976 / 30.00

50

59.94 / 60

74.25

74.17/ 74.25

74.25

148.5

HDTV 1080I

HDTV 1080P

HDTV 1080P

148.35/ 148.50 HDTV 1080P

Remark



11.2 EDID Data

- HDMI EDID - Product ID : 22253 ( HDMI1 and HDMI2 have the Same EDID)

1) HDMI1

2) HDMI2

1) All data are HEXA

2) Adjustable Data :

*: Serial No.

**: week

***: year ex) when year 2008 : input “12”

**** : CHECK SUM (deferent along Serial No, week, year)

- 11 -



ADJUSTMENT INSTRUCTION

1. Application

1) This spec sheet is applied all of the LCD TV with LD84J 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

5. Click "Auto" tab and set as below

6. Click "Run".

7. After downloading, check "OK" message.

(6)

filexxx.bin

(7) .OK

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 Unit: 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 Utility" 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.

(5)

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_INPUT)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)].

(1) (3)

(2) OK

4. Click "Read" tab, and then load download file(XXXX.bin) by clicking "Read"

(4)

filexxx.bin

Adjustment pattern (PC )

• Adjust by commanding AUTO_COLOR_ADJUST(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”.



3.2.1COMPONENT input ADC

3.2.1.1Component Gain/Offset Adjustment

• Convert to Component in Input-source

I2C COMMAND :0xF4(SELECT_INPUT)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 AUTO_COLOR_ADJUST(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 AUTO W/B

EQUIPMENT..

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(M237WD-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



5. Adjustment Command

5.1 Adjustment Commands(LEMGTH=84)

No. Adjustment Contents CMD ADR VAL Description

2

3

4

FACTORY OFF

EEPROM ALL INIT.

EEPROM Read

E0 00 00

Factory mode on

E2 00 00 Factory mode off

E4 00 00

E7 00 00

EEPROM All c lear

EEPROM Read

EEPROM Write by so me values 5 EEPROM Write

6

COLOR SAVE (R/G/B cutoff)

Drive, Contrast, Bright)

E8 00 Data

00 Color

H POSITION

9 CLOCK

10 PHASE

They have different

30 00 00~100 range mode, FOS Adjustment

90 00 00~100

92 00 00~100

16 00 00~FF

18 00 00~FF

Drive adjustment

80 00 00~7F

82 00 00~7F

Offset adjustment

84 00 00~7F

17 BRIGHT

19 CONTRAST

10 00 00~3F

Bright adjustment

12 00 00~64

Luminance adjustment

20 AUTO_COLOR_ ADJU ST F1 00 02 Auto COLOR Adjustment

0: COOL

21

F2

1: NORMAL

2: WARM

3: USER

22 FACTORY_DEFAULT F3 00

Factory mode off

& II_SW is 1

& Input change to TV

0 : TV

1 : AV1

2 : AV2

23

AUTO_INPUTCHANGE F4 00 0,1,2,4

3 : Component

4 : RGB

5 : DVI

6 : HDMI

5.2 EEPROM DATA READ

5.2.1 Signal Table

START 6E

A

50

A

84

A

03 A CMD A ADH A ADL

A

CS

A

STOP

----------------------------------------------------------------------

Dn

A

STOP

128 Bytes

5.2.2 Command Set

Adjustment Details

1 EEPROM READ E7 A0 0 0-Page 0~7F Read

2

3

4

5

6

7

8

80 0-Page 80~FF Read

A2 0 1-Page 0~7F Read

A4

A6


0 2-Page 0~7F Read


0

80

3-Page 0~7F Read

3-Page 80~FF Read

*use: To read the appointment Address of E

5.3 E2PROM Data Write

5.3.1 Signal Table

START 6E

A

50 A 84+n

A

03 A CMD A ADH A

ADL A

Data_1

A

. . . Data_n A CS A STOP

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

No.

Adjustment contents CMD(hex) LEN

1 EEPROM WRITE E8 94

2

Details

16-Byte Write

84+n n-byte Write

- 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)

START 6E A 50 A 84 A 03 A 70 A 00 A 00 A CS A STOP

• 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)

START 6F A Data1 . . . Data128 A CS NA STOP



Check P700 All

Voltage Level (5V, 15V)

Y

TROUBLESHOOTING

1. Power- Up Boot Fail Trouble Shooting

N N

Check Pow er con nector

OK ?

Replace Po wer board

N

Check Q702 Outp ut

Voltage Level (5V)

Y

Check IC705 #2 Pin

Voltage Level 3.3V

Y

N

Replace Q702

Replace IC 705 &

Recheck

N

Check X101 Clock

12MHz

Y

Replace X 101

Replace IC 106 Flash

Memory


- 15 -

Wave form of X101


2. No OSD Trouble Shooting

Check P70 0(#9)

INV_ON high

Y

N

1. Check Po wer Board , 15V

2. Check Q702 Output voltage(5V)

3. Check P302(#1, 2, 3) 5V

Y

N

Check P30 2

#8(TXEC+) , #9(TXEC-) ,

#20(TXOC+) , #21(TXOC-)

Y

Check L VDS Cable for damage or ope n con ductors .

Y

N

N

Check L CD Module

Control board

(Refer to Module CAS)

Check GPIO Path

(Refer to Appe ndix 1 .)

1. Replace Pow er Board

2. Replace Q702

IC101 has problem

Replace Ca ble



3. Digital TV Video Trouble Shooting

Check RF Ca ble

Y

Check Tu ner 5V Po wer &

Q707 5V

Y

N

Replace Q7 07

Bad Tun er. Replace Tuner.

Check L D400 color

None

Check T P Clock, Data, Sync

R440, R441, R442

Y

Check Demod ulator Input Clock

X400 (25MHz)

Y

Check IC10 1 LVDS output

#8(TXEC+) , #9(TXEC-) ,

#20(TXOC+) , #21(TXOC-)

Y

Check L CD Module

Control board

Refer to Mo dule CAS

N

N

N

Maybe Tun er(TU400) has problems

Replace X400

Replace IC101 has problems


- 17 -

Wave form of X400


4. Component Video Trouble Shooting

Check inpu t signal for mat

Is it supported?

Y

Check Compo nent Cab le

Y

Check J K602

Y

Check signal

C124, C126, C129

Y

N

Replace JK602 or Che ck Divice

N

Check R10 7, R109, R112,

C124, C126, C129

IC101 has problem

Wave form of Comp Y

Wave form of Comp Pb

Wave form of Comp Pr

Wave form of C124


Wave form of C126

- 18 -

Wave form of C129


Check inpu t signal format

Is it supported?

Y

Check RGB Cable connector for damage

Y

5. RGB Video Trouble Shooting

N

Replace JK607

Check JK607

Y

Check signal , Hsync, Vsync

(R673, R674)

Y

Check signal RGB

(R119, R104, R105

C121,C122,C119)

Y

N

N

Replace R6 73, R674

Replace R119, R104, R105,

C121,C122,C119

IC101 has problem

Wave form of R673(Vsync)

Wave form of R673(Vsync)

Wave form of R105/C122



- 19 -



Check inpu t signal for mat

Is it supported?

Y

6. AV Video Trouble Shooting

Check AV Ca ble / S-Video Cable f or damage or ope n conn ector

Y

N

Check signal R611(AV_CVBS),

R625, R626(S_Video)

Y

Check signal RGB

R116, R113, R114

C137, C134, C135

Y

N

Replace R6 11, R625, R626

Replace R1 16, R113, R114

C137, C134, C135

IC101 has problem

Wave form of R611(CVBS)

Wave form of R625(S-video) Wave form of R626(S-video)



7.HDMI Video Trouble Shooting

Check input signal form at

Is it supported?

Y

Check HD MI Cable for damage o r open conn ecto r

Y

Check JK801 / JK802 for proper connectio n or dam age

Y

Check IC803 Out Volta ge Level

3.3V(Pin 6)

Y

Check ED ID NVRAM

(IC801, IC802)

Power & I2 C Sig nal (#5, #6)

Y

Check HD CP Key NVRAM (IC105)

Power & I2 C Sig nal (#5, #6)

Y

N

N

N

N

Replace Ms tar (IC101)

Replace c onn ector

Replace IC803

Redownloa d EDID data or

Rep

Replace IC105



8. All Source Audio Trouble Shooting

Make sure yo u can t hear any audi o and Device sup port the au di o sig nal norm ally .

Y

Check Speaker and it s w ire con nectio n (P500)

An d the resistance

Y

N

Replace co nnector or Speaker

Check 15V From Po wer board

(P700, Pin #1,2)

An d Check Aud io Amp Pow er 12V

(IC501, Pin#2, 3, 3 4, 35, 40, 41, 44, 45)

Y

N

N

Check Sig nal from IC501

L502, L503, L504, L505

Y

N

Check Sig nal from IC101

(R130, R131, R1021, R1022)

Replace P ower Board or Check

L511

Replace IC 500

Replace IC 101



Appendix 1. GPIO Path.



BLOCK DIAGRAM



DESCRIPTION OF BLOCK DIAGRAM

1.Input Interface.

1-1.PC Input

- RGB Input is directly transmitted to LGE1854C(scaler,Clock 12Mhz) and display up to 1920*1080 resolution

- DVI Signal input go to scaler through TMSD351(DVI/HDMI Switch)

- PC Audio is connected PC-Audio input by Stereo Cable

1-2 Video Input

- Component :YPbPr/YCbCr signal input, Up to 1080P Resolution.

- CVBS/S-Video : CVBS/S-Video signal input, supporting 480P

- HDMI 1,2 :Digital signal input(Included Audio)

1-3 RF(ATSC/NTSC)Input :ATSC/NTSC Input.

1-4 Audio Input :Component L/R,Audio L/R,Stereo(For PC) input.

2.Output Interface

- Video :The video signal goes to LGE1854C(Scaler)-> Frame Memory(210MHz:converted LVDS signal)->Module

- Audio :The audio is divided Digital signal at Scaler go through NTP3000A(Audio Amp IC) and generate to Speaker

Head-phone signal is divided to stereo signal at Scaler, then generate Headphone Amp(IC TPA6110)

- Optical Output :Generate audio output from Scaler(SPDIF(Optical)

3.Power Interface

- Input 5V,15V from Power Board is converted to 3.3V,2.6V,1.8V,1.25V,1.2V by Regulator and DC/DC Converter

Supply power to Module,Audio Amp and IC



EXPLODED VIEW

IMPORTANT SAFETY NOTICE

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 X-RADIATION, Shock, Fire, or other Hazards.

Do not modify the original design without permission of manufacturer.

Copyright LG Electronics. Inc. All right reserved.



SCHEMATIC DIAGRAM

MAIN



DDR



TUNER/ DEMODULELATOR



LVDS/ CONTROL



INTERFACE



POWER



HDMI / DVI



AMP



LED_IR_HP



CONTROL KEY



P/NO : MFL49414510

Jan., 2009

Printed in Korea

LG LD84J M237WD, M237WD-PMJ LCD monitor TV SERVICE MANUAL

Assistant Bot

North/Latin America

Europe/Africa

Asia/Oceania

Internal Use Only

http://aic.lgservice.com

http://eic.lgservice.com

http://biz.lgservice.com

LCD MONITOR TV

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE CHASSIS,

READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

CONTENTS

SAFETY PRECAUTIONS

General Guidance

SERVICING PRECAUTIONS

SPECIFICATION

1. Application Range.

3.Test method

2. Specification

4. General Specification

5. Optical characteristic specification

6. SET Optical Feature

7. Mechanical specification

8. Component Video Input (Y, P

, P

)

10. RGB/DVI

12. HDMI1,2

ADJUSTMENT INSTRUCTION

1. Application

2. Designation

3. Main PCB check process

4. Total Assembly line process

5. Adjustment Command

Check P700 All

Voltage Level (5V, 15V)

Y

TROUBLESHOOTING

N N

Check Pow er con nector

OK ?

Replace Po wer board

N

Check Q702 Outp ut

Voltage Level (5V)

Y

Check IC705 #2 Pin

Voltage Level 3.3V

Y

N

Replace Q702

Replace IC 705 &

Recheck

N

Check X101 Clock

12MHz

Y

Replace X 101

Replace IC 106 Flash

Memory

Check P70 0(#9)

INV_ON high

Y

N

1. Check Po wer Board , 15V

2. Check Q702 Output voltage(5V)

3. Check P302(#1, 2, 3) 5V

Y

N

Check P30 2

#8(TXEC+) , #9(TXEC-) ,

#20(TXOC+) , #21(TXOC-)

Y

Check L VDS Cable for damage or ope n con ductors .

Y

N

N