LG 55LH90QD Schematic

LED LCD TV

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

CHASSIS : LT91C

MODEL : 55LH90QD

55LH90QD-DC

North/Latin America http://aic.lgservice.com Europe/Africa http://eic.lgservice.com Asia/Oceania http://biz.lgservice.com

Internal Use Only

P/NO : MFL62149713(0907-REV00) Printed in Korea

Only for training and service purposes

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CONTENTS

CONTENTS .............................................................................................. 2

PRODUCT SAFETY ..................................................................................3

SPECIFICATION ........................................................................................6

ADJUSTMENT INSTRUCTION ...............................................................12

BLOCK DIAGRAM...................................................................................18

EXPLODED VIEW .................................................................................. 19

SVC. SHEET ...............................................................................................

Only for training and service purposes

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SAFETY PRECAUTIONS

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the Schematic Diagram and Exploded View. It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer.

General Guidance

An isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC power line. Use a transformer of adequate power rating as this protects the technician from accidents resulting in personal injury from electrical shocks.

It will also protect the receiver and it's components from being damaged by accidental shorts of the circuitry that may be inadvertently introduced during the service operation.

If any fuse (or Fusible Resistor) in this TV receiver is blown, replace it with the specified.

When replacing a high wattage resistor (Oxide Metal Film Resistor, over 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, CONDUIT etc.

AC Volt-meter

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

*Base on Adjustment standard

IMPORTANT SAFETY NOTICE

0.15uF

Ω

Only for training and service purposes

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CAUTION: Before servicing receivers covered by this service manual and its supplements and addenda, read and follow the

SAFETY PRECAUTIONS on page 3 of this publication. NOTE: If unforeseen circumstances create conflict between the

following servicing precautions and any of the safety precautions on page 3 of this publication, always follow the safety precautions. Remember: Safety First.

General Servicing Precautions

1. Always unplug the receiver AC power cord from the AC power source before; a. Removing or reinstalling any component, circuit board

module or any other receiver assembly.

b. Disconnecting or reconnecting any receiver electrical plug or

other electrical connection.

c. Connecting a test substitute in parallel with an electrolytic

capacitor in the receiver. CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard.

2. Test high voltage only by measuring it with an appropriate high voltage meter or other voltage measuring device (DVM, FETVOM, etc) equipped with a suitable high voltage probe. Do not test high voltage by "drawing an arc".

3. Do not spray chemicals on or near this receiver or any of its assemblies.

4. Unless specified otherwise in this service manual, clean electrical contacts only by applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or comparable non-abrasive applicator; 10% (by volume) Acetone and 90% (by volume) isopropyl alcohol (90%-99% strength) CAUTION: This is a flammable mixture. Unless specified otherwise in this service manual, lubrication of contacts in not required.

5. Do not defeat any plug/socket B+ voltage interlocks with which receivers covered by this service manual might be equipped.

6. Do not apply AC power to this instrument and/or any of its electrical assemblies unless all solid-state device heat sinks are correctly installed.

7. Always connect the test receiver ground lead to the receiver chassis ground before connecting the test receiver positive lead. Always remove the test receiver ground lead last.

8. Use with this receiver only the test fixtures specified in this

service manual.

CAUTION: Do not connect the test fixture ground strap to any heat sink in this receiver.

Electrostatically Sensitive (ES) Devices

Some semiconductor (solid-state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor "chip" components. The following techniques should be used to help reduce the incidence of component damage caused by static by static electricity.

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed to prevent potential shock reasons prior to applying power to the

unit under test.

2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.

4. Use only an anti-static type solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges sufficient to damage ES devices.

5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.

6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material).

7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed. CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ES device.)

General Soldering Guidelines

1. Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape that will maintain tip temperature within the range or 500

°F to 600°F.

2. Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40 parts lead.

3. Keep the soldering iron tip clean and well tinned.

4. Thoroughly clean the surfaces to be soldered. Use a mall 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.

(500

°F to 600°F)

b. Heat the component lead until the solder melts. c. Quickly draw the melted solder with an anti-static, suction-

type solder removal device or with solder braid. CAUTION: Work quickly to avoid overheating the circuit board printed foil.

6. Use the following soldering technique. a. Allow the soldering iron tip to reach a normal temperature

(500

°F to 600°F)

b. First, hold the soldering iron tip and solder the strand against

the component lead until the solder melts.

c. Quickly move the soldering iron tip to the junction of the

component lead and the printed circuit foil, and hold it there only until the solder flows onto and around both the component lead and the foil. CAUTION: Work quickly to avoid overheating the circuit board printed foil.

d. Closely inspect the solder area and remove any excess or

splashed solder with a small wire-bristle brush.

SERVICING PRECAUTIONS

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.

Replacement

1. Carefully insert the replacement IC in the circuit board.

2. Carefully bend each IC lead against the circuit foil pad and solder it.

3. Clean the soldered areas with a small wire-bristle brush. (It is not necessary to reapply acrylic coating to the areas).

"Small-Signal" Discrete Transistor Removal/Replacement

1. Remove the defective transistor by clipping its leads as close as possible to the component body.

2. Bend into a "U" shape the end of each of three leads remaining on the circuit board.

3. Bend into a "U" shape the replacement transistor leads.

4. Connect the replacement transistor leads to the corresponding leads extending from the circuit board and crimp the "U" with long nose pliers to insure metal to metal contact then solder each connection.

Power Output, Transistor Device Removal/Replacement

1. Heat and remove all solder from around the transistor leads.

2. Remove the heat sink mounting screw (if so equipped).

3. Carefully remove the transistor from the heat sink of the circuit board.

4. Insert new transistor in the circuit board.

5. Solder each transistor lead, and clip off excess lead.

6. Replace heat sink.

Diode Removal/Replacement

1. Remove defective diode by clipping its leads as close as possible to diode body.

2. Bend the two remaining leads perpendicular y to the circuit board.

3. Observing diode polarity, wrap each lead of the new diode around the corresponding lead on the circuit board.

4. Securely crimp each connection and solder it.

5. Inspect (on the circuit board copper side) the solder joints of the two "original" leads. If they are not shiny, reheat them and if necessary, apply additional solder.

Fuse and Conventional Resistor Removal/Replacement

1. Clip each fuse or resistor lead at top of the circuit board hollow stake.

2. Securely crimp the leads of replacement component around notch at stake top.

3. Solder the connections. CAUTION: Maintain original spacing between the replaced component and adjacent components and the circuit board to prevent excessive component temperatures.

Circuit Board Foil Repair

Excessive heat applied to the copper foil of any printed circuit board will weaken the adhesive that bonds the foil to the circuit board causing the foil to separate from or "lift-off" the board. The following guidelines and procedures should be followed whenever this condition is encountered.

At IC Connections

To repair a defective copper pattern at IC connections use the following procedure to install a jumper wire on the copper pattern side of the circuit board. (Use this technique only on IC connections).

1. Carefully remove the damaged copper pattern with a sharp knife. (Remove only as much copper as absolutely necessary).

2. carefully scratch away the solder resist and acrylic coating (if used) from the end of the remaining copper pattern.

3. Bend a small "U" in one end of a small gauge jumper wire and carefully crimp it around the IC pin. Solder the IC connection.

4. Route the jumper wire along the path of the out-away copper pattern and let it overlap the previously scraped end of the good copper pattern. Solder the overlapped area and clip off any excess jumper wire.

At Other Connections

Use the following technique to repair the defective copper pattern at connections other than IC Pins. This technique involves the installation of a jumper wire on the component side of the circuit board.

1. Remove the defective copper pattern with a sharp knife. Remove at least 1/4 inch of copper, to ensure that a hazardous condition will not exist if the jumper wire opens.

2. Trace along the copper pattern from both sides of the pattern break and locate the nearest component that is directly connected to the affected copper pattern.

3. Connect insulated 20-gauge jumper wire from the lead of the nearest component on one side of the pattern break to the lead of the nearest component on the other side. Carefully crimp and solder the connections. CAUTION: Be sure the insulated jumper wire is dressed so the it does not touch components or sharp edges.

Only for training and service purposes

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SPECIFICATION

NOTE : Specifications and others are subject to change without notice for improvement

.

4. Electrical specification

4.1 Module General Specification

1. Application range

This specification is applied to the 55” LCD TV used LT91C chassis.

2. Requirement for Test

Each part is tested as below without special appointment.

1) Temperature : 25±5ºC (77±9ºF), CST : 40±5ºC

2) Relative Humidity : 65±10%

3) Power Voltage : Standard input voltage (100-240V@50/60Hz) * Standard Voltage of each products is marked by models.

4) Specification and performance of each parts are followed

each drawing and specification by part number in accordance with BOM.

5) The receiver must be operated for about 5 minutes prior to

the adjustment.

3. Test method

1) Performance: LGE TV test method followed

2) Demanded other specification

- Safety: CE / ICE specification EMI: CE / ICE

No Item Specification Remark

1 Screen Device 55” wide Color Display module LCD

2 Aspect Ratio 16:9

3 LCD Module 55”TFT LCD FHD 240Hz MAKER : 55”-LGD (FHD/240Hz)

4 Operating Environment

Temp.: 0 ~ 50°C 240h

Humidity : Ta=40°C, 90%RH, 240h

5 Storage Environment Temp.: -20 ~ 60°C 240h

6 Input Voltage AC100-240V~, 50/60Hz

7 Power Consumption

Power on (Green)

LCD(Module) + Backlight(LED)

Typ : 237 W

8 Module Size 1286.0 (H) x 745.0 (V) x 65.0 (D) With inverter

9 Pixel Pitch 0.63000 (H) x 0.63000 (V)

10 Back Light LED

11 Display Colors 1.06Billion (10 bit)

12 Coating 3H, Semi-glare

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Only for training and service purposes

4.2 MODEL General Specification

No Item Specification Remarks

1 Market Taiwan

Digital DVB-T UHF 14-69

2 Broadcasting

Analog NTSC-M

3 Receiving Analog Upper Heterodyne

system Digital COFDM,QAM

4 Video Input RCA (2EA) NTSC

5 Component Input (2EA)

Y/Cb/Cr

Y/Pb/Pr

6 RGB Input RGB-PC

HDMI1-DTV/DVI PC(HDMI version 1.3) / DTV format, Support HDCP

7 HDMI Input (4EA)

HDMI2-DTV DTV format, Support HDCP

HDMI3-DTV DTV format, Support HDCP

HDMI4-DTV DTV format, Support HDCP

8 Audio Input (5EA) RGB/DVI Audio, Component1/2, AV1/2

RGB/DVI Audio : Stereo Phone Jack

Others : RCA Jack

9 SDPIF out (1EA) Optical Audio out

10 USB (1EA) USB2.0 JPEG, MP3, DivX, and SVC (download)

5. Chroma& Brightness

5.1 Module optical specification

*** LGD module Uniformity Measurement Position*** ** LED Backlight Contrast Ratio Measurement Condition **

P1

P2

P3

P4

P5

1W/4

2W/4

3W/4

1H/4

2H/4

3H/4

: Measurement position (5 point)

P1

P2

P1 (red point) : Measure the white in a center point of box and the Black in a edge point of screen P2 (green point) : Measure the white and black near of box The CR of full black and white is 2,000,000:1 and local dimming

measurement that P1 is 10,000: 1 and P2 is 1000:1 in the 16% window

** reference ** The measurements of Local Dimming are doing by this case Case 1 : P1:10,000: 1 , P2 :1000:1 in 25% window over 100 Blocks Case 2 : P1:10,000: 1 , P2 :1000:1 in 16% window under 100 Blocks

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Only for training and service purposes

1) Optical characteristics are determined after the unit has been ‘ON’ and stable in a dark environment at 25±2°C

2) Surface luminance is the luminance value at center 1-point across the LCD surface 50cm from the surface with all pixels displaying white.

No. Item Specification Min. Typ. Max. Remark

1. Viewing Angle<CR>10> Right/Left/Up/Down 178 CR > 10

Luminance (cd/m

2

)400 500

PSM: Vivid, CSM: Cool

2. Luminance White (100IRE)

Variation - 1.3

3. Contrast Ratio CR 900 1300 All white/ All black

White WX 0.279

WY Typ 0.292 Typ

RED Xr - 0.03 0.649 +0.03 PSM: Vivid, CSM: Cool

4. CIE Color Coordinates Yr 0.323 White (85IRE)

Green Xg 0.290

Yg 0.637

Blue Xb 0.147

Yb 0.057

5.2 55”LCD Module (LGD)-LC550WUL-SBM1

No Item Min Typ Max Remark

1. Cool

White Balance,X axis 0.274 0.276 0.278

White Balance,Y axis 0.281 0.283 0.285 PSM: Vivid, CSM: Cool,

2. Medium

White Balance,X axis 0.283 0.285 0.287 White (85IRE)

White Balance,Y axis 0.291 0.293 0.295 Dynamic contrast: off, Dynamic color: off

3. Warm

White Balance,X axis 0.311 0.313 0.315

White Balance,Y axis 0.327 0.329 0.331

6. Chroma (PSM:Vivid, Color Temperature:Cool)

– except “RGB PC Mode PSM: Standard, Color Temperature:Medium” ** The W/B Tolerance is ±0.015

7. SET Optical Feature

7.1 General feature

(Measurement Condition: Full white/ Vivid -> Measure the black luminance after 30 seconds.

7.2 Special feature

Dynamic CR 40000:1 -> Measure the black luminance after 30 seconds.

No Item

Luminance(min) C/R(min)

Remark

AV,COMPONENT,HDMI AV,COMPONENT,HDMI

1 55 inch 400 cd/m

2

900 exxcept from the PC mode.

No Item Min Typ Max Remark

1

Dynamic CR

1,800,000 2,000,00

HDMI 720p Full Black pattern

(Only HDMI mode)

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Only for training and service purposes

8. POWER

No Item Min Typ Max Unit Remarks

1. AC Power Shut Down Voltage 90 264 Vac

42” 21.6 24 26.4 Vdc

2 DC Voltage,Inverter 47” 21.6 24 26.4 Vdc

55” 21.6 24 26.4 Vdc

42” 11.4 12.0 12.6 Vdc

3. DC Voltage,LCD Panel 47” 11.4 12.0 12.6 Vdc

55” 21.6 24 26.4 Vdc

4. DC Voltage,Stand By 4.94 5.2 5.46 Vdc

DC Voltage,Sound AMP (24V) 24 Vdc 42/47/55LH90QD-DC

5. DC Voltage,Sound AMP (3.3V) 2.97 3.3 3.63 Vdc ALL

DC Voltage,Sound AMP (1.8V) 1.62 1.8 1.98 Vdc ALL

6.

DC Voltage,Tuner (3.3V) 3.1 3.3 3.5

DC Voltage,Tuner (1.8V) 1.6 1.8 2.0 Vdc

DC Voltage,Mstar (3.3V) 3.1 3.3 3.5 Vdc

7. DC Voltage,Mstar (1.8V) 1.6 1.8 2.0 Vdc

DC Voltage,Mstar (1.26V) 1.06 1.26 1.46 Vdc LGE3369

DC Voltage,Mstar (3.3V) 3.1 3.3 3.5 Vdc

8. DC Voltage,Mstar (1.8V) 1.6 1.8 2.0 Vdc

DC Voltage,Mstar (1.26V) 1.06 1.26 1.46 Vdc LGE7329

9.

DC Voltage,Local Dimming (3.3V) 3.1 3.3 3.5 Vdc

DC Voltage,Local Dimmin (1.8V) 1.6 1.8 2.0 Vdc LGE5110

No Item Min Typ Max Unit Remarks

1. Video Input Level 0.9 1 1.1 Vpp

2. Audio Input Level 0.4 0.5 0.6 Vrms PAL

3. Component Video Input Level (Y,C

B/PB,CR/PR) 0.6 0.7 0.8 Vpp

4. R/G/B Video Input Level, 0.6 0.7 0.8 Vpp

9. Standard Level For Input Signal (Video,Audio,Y/C,Component,RGB)

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Only for training and service purposes

10. Component Video Input (Y, CB/PB, CR/PR)

No

Specification

Remark

Resolution H-freq(kHz) V-freq(Hz)

1. 720x480 15.73 60.00 SDTV,DVD 480i

2. 720x480 15.63 59.94 SDTV,DVD 480i

3. 720x480 31.47 59.94 480p

4. 720x480 31.50 60.00 480p

5. 720x576 15.625 50.00 SDTV,DVD 625 Line

6. 720x576 31.25 50.00 HDTV 576p

7. 1280x720 45.00 50.00 HDTV 720p

8. 1280x720 44.96 59.94 HDTV 720p

9. 1280x720 45.00 60.00 HDTV 720p

10. 1920x1080 31.25 50.00 HDTV 1080i

11. 1920x1080 33.75 60.00 HDTV 1080i

12. 1920x1080 33.72 59.94 HDTV 1080i

13. 1920x1080 56.250 50 HDTV 1080p

14. 1920x1080 67.43/67.5 59.94/60 HDTV 1080p

No

Specification

Proposed Remark

Resolution H-freq(kHz) V-freq(Hz) Pixel Clock(MHz)

1. 720*400 31.468 70.08 28.321 For only DOS mode

2. 640*480 31.469 59.94 25.17 VESA

Input 848*480

60Hz, 852*480 60Hz

-> 640*480 60Hz Display

3. 800*600 37.879 60.31 40.00 VESA

4. 1024*768 48.363 60.00 65.00 VESA(XGA)

5. 1280*768 47.78 59.87 79.5 WXGA

6. 1360*768 47.72 59.8 84.75 WXGA

7. 1280*1024 63.595 60.0 108.875 SXGA FHD model

8. 1920*1080 66.587 59.93 138.625 WUXGA FHD model

11. RGB (PC)

12. HDMI Input (PC/DTV)

12.1 DTV Mode

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

1. 720*480 31.469 /31.5 59.94 / 60 27.00/27.03 SDTV 480P

2. 720*576 31.25 50 54 SDTV 576P

3. 1280*720 37.500 50 74.25 HDTV 720P

4. 1280*720 44.96 / 45 59.94 / 60 74.17/ 74.25 HDTV 720P

5. 1920*1080 33.72 / 33.75 59.94 / 60 74.17/ 74.25 HDTV 1080I

6. 1920*1080 28.125 50.00 74.25 HDTV 1080I

7. 1920*1080 26.97 / 27 23.97 / 24 74.17/ 74.25 HDTV 1080P

8. 1920*1080 33.716 / 33.75 29.976 / 30.00 74.25 HDTV 1080P

9. 1920*1080 56.250 50 148.5 HDTV 1080P

10. 1920*1080 67.43 / 67.5 59.94 / 60 148.35/148.50 HDTV 1080P

- 11 -

Only for training and service purposes

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

1. 720*400 31.468 70.08 28.321 HDCP

2. 640*480 31.469 59.94 25.17 VESA HDCP

3. 800*600 37.879 60.31 40.00 VESA HDCP

4. 1024*768 48.363 60.00 65.00 VESA(XGA) HDCP

5. 1280*768 47.78 59.87 79.5 WXGA HDCP

6. 1360*768 47.72 59.8 84.75 WXGA HDCP

7. 1280*1024 63.595 60.0 108.875 SXGA HDCP

8. 1920*1080 67.5 60 148.5 WUXGA HDCP

12.2 PC Mode

No Item Content Unit Remark

Width(W) Length(L) Height(H)

W/O Packing

1373 454.2 964.3 mm With Stand

1 Product

1373 106.9 888.5 mm W/O Stand

Dimension

1485 570 1063 mm With Stand

With Packing

1485 355 1012 mm W/O Stand

W/O Packing

40.9 Kg With Stand

2 Product 35.5 Kg W/O Stand

Weight

With Packing

46.6 Kg With Stand

4.1 Kg W/O Stand

Cintaniner 40ft(Normal) 40ft(H-Cubic)

3 Loding

Individual

W/O stand With stand W/O stand With stand

Quantity 64 96 64 96

Swivel YES

Function

Angle ±20° Degree

Tilt NO

Angle - Degree

Width Depth Height

4 Stand Assy Dimension 572 454.2 276.2 mm With Neck

(W/O Packing) -- -- mm W/O Neck

Dimension

(With Packing)

-- -- -- mm Commercial

Weight(W/O Packing) -- -- 5.4 Kg With Neck

Weight(With Packing) -- -- -- Kg

5 Appearance Refer to Standard of LG(56)G4-9002

13. Mechanical specification

Only for training and service purposes

- 12 -

ADJUSTMENT INSTRUCTION

1. Application Range

This specification sheet is applied to all of the LCD TV with LT91C chassis.

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 5 Minutes (Heat Run)

Temperature : at 25±5ºC Relative humidity : 65±10% Input voltage : 220V, 60Hz

6) Adjustment equipments: Color Analyzer (CA-210 or CA-

110), Pattern Generator(MSPG-925L or Equivalent), DDC Adjustment Jig equipment, SVC remote controller

7) Push The “IN STOP KEY” - For memory initialization.

3. Main PCB check process

* APC - After Manual-Insert, executing APC

* Boot file 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 “Error” is displayed, Check connection between computer, jig, and set..

(3) Click “Read” tab, and then load download file (XXXX.bin)

by clicking “Read”.

(4) Click “Connect” tab. If “Can’t” is displayed, check

connection between computer, jig, and set.

(5) Click “Auto” tab and set as below (6) Click “Run”. (7) After downloading, check “OK” message.

filexxx.bin

(7)

(5)

(8) ……….OK

(6)

(1) (3)

Please Check the Speed :

To use speed between

from 200KHz to 400KHz

(4)

filexxx.bin

Case1 : Software version up

1. After downloading S/W by USB, TV set will reboot automatically

2. Push “In-stop” key

3. Push “Power on” key

4. Function inspection

5. After function inspection, Push “I n-stop” key.

Case2 : Function check at the assembly line

1. When TV set is entering on the assembly line, Push “In-stop” key at first.

2. Push “Power on” key for turning it on.

-> If you push “Power on” key, TV set will recover channel information by itself.

3. After function inspection, Push “In-stop” key.

* USB DOWNLOAD(*.epk file download)

(1) Put the USB Stick to the USB socket. (2) Automatically detecting update file in USB Stick.

- If your downloaded program version in USB Stick is Low, it didn’t work. But your downloaded version is High, USB data is automatically detecting

(3) Show the message “Copying files from memory”

(4) Updating is staring.

(5) After updating is complete, The TV will restart automatically. (6) If TV turns on, check your updated version and Tool

option. (refer to the next page about tool option)

* If downloading version is higher 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 "IN-START" key in service remote controller.

2. Select "Tool Option 1" and Push “OK” button.

3. Punch in the number. (Each model has their number.)

4. Completed selecting Tool option.

3.1. ADC Process

• Input signal : Component

• Signal equipment displays

Adjustment pattern

- Component 480I MODEL: 209 in Pattern Generator(480i Mode) PATTERN : 65 in Pattern Generator(MSPG-925 SERIES)

• Input Signal : RGB (You don’t need to connect RGB Cable).

Because We use TV internal pattern.

• After enter Service Mode by pushing “ADJ” key,

• Enter Internal ADC mode by pushing “G ” key at “5. ADC

Calibration”

*

Caution: Using ‘power on’ button of the Adj. R/C, power on TV.

* ADC Calibration Protocol (RS232)

* Adjustment can be done using only external ADC * Required equipment : Adjustment R/C. * Down Load data of picture

This process must do in using the LED model

- Push the button “Power Only “ key in Adjust remote control

- Push the button “ Exit” key in Adjust remote control

3.2. Function Check

(1) Check display and sound

- Check Input and Signal items. (cf. work instructions)

1) TV

2) AV (CVBS)

3) COMPONENT (480i)

4) RGB (PC : 1024 x 768 @ 60hz)

5) HDMI

6) PC Audio In

* Display and Sound check is executed by remote control.

- 13 -

Only for training and service purposes

Model Tool option1 Tool option2 Tool option3 Tool option4

42LH90QD 25411 3144 55462 20736

47LH90QD 33603 3144 55462 20736

55LH90QD 45891 3144 55462 20736

i TV Software Upgrade

Upgrading...

Do not plug off!

63%

i TV Software Upgrade

Upgrading COMPLETED

The TV will restart after seconds.

100%

EZ ADJUT

0. Tool Option1

1. Tool Option2

2. Tool Option3

3. Tool Option4

4. Country Group

5. ADC Calibration

6. White Balance

7. Test Pattern

8. EDID D/L

9. Sub B/C

10. V-Com

11. P-Gamma

ADC Calibration

ADC Comp 480i

ADC Comp 1080p

ADC RGB

NG

Reset

Start

i TV Software Upgrade

Copying files from memory

Do not remove the memory card from the pc

Do not plug off!

NO Item

CMD1 CMD2

Data0 Data 1

1 Main total mode A A 0 0 0 0

2 Change to Component X B 0 0 4 0

3 Adjust Component A D 0 0 1 0

4 Change to RGB X B 0 0 6 0

5 Adjust RGB A D 0 0 1 0

4. Total Assembly line process

4.1. Adjustment Preparation

· W/B Equipment condition CA210 : CH 14(LED), Test signal : Inner pattern (85IRE)

· Above 5 minutes H/run in the inner pattern. (“power on” key

of adjust remote control)

4.1.1 Connecting picture of the measuring instrument

(On Automatic control) Inside PATTERN is used when W/B is controlled. Connect to auto controller or push Adjustment R/C POWER ON -> Enter the mode of White-Balance, the pattern will come out

4.1.2 Auto-control interface and directions

1) Adjust in the place where the influx of light like floodlight

around is blocked. (illumination is less than 10ux).

2) Adhere closely the Color Analyzer (CA210) to the module

less than 10cm distance, keep it with the surface of the Module and Color Analyzer’s Prove vertically.(80~100°).

3) Aging time

- After aging start, keep the power on (no suspension of power supply) and heat-run over 15minutes.

- Using ‘no signal’ or ‘full white pattern’ or the others, check the back light on.

4.1.3 Auto adjustment Map (only RS-232C)

RS-232C COMMAND [CMD format]

- LEN: Number of Data Byte to be send

- CMD: Command

- VAL: FOS Data

- CS: Checksum of sent Data

- A: Acknowledge

Ex) [Send: JA_00_DD] / [Ack: A_00_okDDX]

[ CMD ID DATA ] Wb 00 00 White Balance Start Wb 00 ff White Balance End

In the SET applied LED module, as to physical characteristics of

LED Module, the sets takes a 120 minutes by aging time to stabilize a color coordinates. So White Balance Control equipments get the SET Aging Time from SET and then going to control the W/B by revise color coordinates in the each time.

-

The Time Table of color coordinates by SET Aging Time

**Caution **

Color Temperature : COOL, Medium, Warm. One of R Gain/G Gain/ B Gain should be kept on 0xC0, and adjust other two lower than C0. (when R/G/B Gain are all C0, it is the FULL Dynamic Range of Module)

- 14 -

Only for training and service purposes

Cool 11,000k ºK X=0.276(±0.002)

Y=0.283(±0.002) <Test Signal>

Medium 9,300k ºK X=0.285(±0.002) Inner pattern

Y=0.293(±0.002) (216gray,85IRE)

Warm 6,500k ºK X=0.313(±0.002)

Y=0.329(±0.002)

Full White Pattern

COLOR ANALYZER TYPE: CA-210

RS-232C Communication

CA-210

START 6E A 50 A LEN A 03 A CMD A 00 A VAL A CS A STOP

RS-232C COMMAND MIN CENTER MAX

[CMD ID DATA] (DEFAULT)

Cool Mid Warm Cool Mid Warm

R Gain jg Ja jd 00 172 192 192 255

G Gain jh Jb je 00 172 192 192 255

B Gain ji Jc jf 00 192 192 172 255

R Cut 64 64 64 128

G Cut 64 64 64 128

B Cut 64 64 64 128

Cool Medium Warm

H/R Time(Min)

axisX axisY axisX axisY axisX axisY

276 283 285 293 313 329

1 0-4 284 301 293 311 313 329

2 5-9 282 296 291 307 312 328

3 10-14 281 291 290 303 310 326

4 15-19 280 288 289 301 308 324

5 20-24 279 286 288 299 307 322

6 25-29 278 285 287 297 306 321

7 30-39 277 284 286 295 305 320

8 40 - 276 283 285 293 304 318

4.2. Manual W/B process using adj. R/C

Dynamic contrast : off Dynamic color : off OPC : Off Energy saving mode : Off

• After enter Service Mode by pushing “ADJ” key,

• Enter White Balance by pushing “

G”

• In the SET applied LED module, as to physical characteristics of LED Module, the sets takes a 120 minutes by aging time to stabilize a color coordinates. So White Balance Control equipments get the SET Aging Time from SET and then going to control the W/B by revise color coordinates in the each time

-

The Time Table of color coordinates by SET Aging Time

* After done all adjustments, Press “In-start” button and

compare Tool option and Area option value with its BOM, if it is correctly same then unplug the AC cable. If it is not same, then correct it same with BOM and unplug AC cable. For correct it to the model’s module from factory JIG model.

* Push The “IN STOP KEY” after completing the function

inspection.

4.3 DDC EDID Write (RGB 128Byte )

· Connect D-sub Signal Cable to D-Sub Jack.

· Write EDID DATA to EEPROM (24C02) by using DDC2B protocol.

· Check whether written EDID data is correct or not.

* For SVC main Ass’y, EDID have to be downloaded to Insert

Process in advance.

4.4 DDC EDID Write (HDMI 256Byte)

· Connect HDMI Signal Cable to HDMI Jack.

· Write EDID DATA to EEPROM(24C02) by using DDC2B protocol.

· Check whether written EDID data is correct or not.

* For SVC main Ass’y, EDID have to be downloaded to Insert

Process in advance.

4.5 EDID DATA

1) All Data : HEXA Value

2) Changeable Data :

*: Serial No : Controlled / Data:01 **: Month : Controlled / Data:00 ***:Year : Controlled ****:Check sum

- Auto Download

· After enter Service Mode by pushing “ADJ” key,

· Enter EDID D/L mode.

· Enter “START” by pushing “OK” key.

* Edid data and Model option download (RS232)

- 15 -

Only for training and service purposes

Cool Medium Warm

H/R Time(Min)

axisX axisY axisX axisY axisX axisY

276 283 285 293 313 329

1 0-4 284 301 293 311 304 318

2 5-9 282 296 291 307 305 320

3 10-14 281 291 290 303 306 321

4 15-19 280 288 289 301 307 322

5 20-24 279 286 288 299 308 324

6 25-29 278 285 287 297 310 326

7 30-39 277 284 286 295 312 328

8 40 - 276 283 285 293 313 329

EZ ADJUT

0. Tool Option1

1. Tool Option2

2. Tool Option3

3. Tool Option4

4. Country Group

5. ADC Calibration

6. White Balance

7. Test Pattern

8. EDID D/L

9. Sub B/C

10. V-Com

11. P-Gamma

EDID D/L

HDMI1

HDMI2

HDMI3

RGB

NG

Reset

Start

EDID D/L

HDMI1

HDMI2

HDMI3

RGB

OK

Reset

Start

EZ ADJUST

0. Tool Option1

1. Tool Option2

2. Tool Option3

3. Tool Option4

4. Country Group

5. ADC Calibration

6. White Balance

7. Test Pattern

8. EDID D/L

9. Sub B/C

10. V-Com

11. P-Gamma

White Balance

Color Temp.

R-Gain G-Gain B-Gain R-Cut G-Cut B-Cut Test-Pattern. Reset

Cool

172 172 192 64 64 64 ON

To set

Item CMD1 CMD2 Data0

Download A A 0 0 When transfer the ‘Mode In’,

‘Mode In’ Carry the command.

Download A E 00 10 Automatically Download

(The use of a internal pattern)

- Manual Download

* Caution

1) Use the proper signal cable for EDID Download

- Analog EDID : Pin3 exists

- Digital EDID : Pin3 exists

2) Nerver connect HDMI & D-sub Cable at the same time.

3) Use the proper cables below for EDID Writing.

4) Download HDMI1, HDMI2 separately because each data is different.

(1) Analog Data 128Byte

* Detail EDID Options are below

Product ID

Month, Year: Controlled on production line:

ex) Monthly : ‘09’ -> ‘09’

Year : ‘2006’ -> ‘10’

Model Name(Hex):

Checksum: Changeable by total EDID data.

(2) Digital Data (HDMI-1/2/3) 256Byte

* Detail EDID Options are below

Product ID

Month, Year: Controlled on production line:

ex) Monthly : ‘09’ -> ‘09’

Year : ‘2006’ -> ‘10’

Model Name(Hex):

Checksum: Changeable by total EDID data. Vendor Specific

- FHD model except

e

d

c

b

a

d

c

b

a

- 16 -

Only for training and service purposes

012 3 4 5 6 7 8 9 A BCD EF

00 00 FF FF FF FF FF FF 00 1E 6D 01 01 01 01

10 01 03 68 73 41 78 0A CF 74 A3 57 4C B0 23

20 09 48 4C A1 08 00 81 80 61 40 45 40 31 40 01 01

30 01 01 01 01 01 01 02 3A 80 18 71 38 2D 40 58 2C

40 45 00 7E 8A 42 00 00 1E 01 1D 00 72 51 D0 1E 20

50 6E 28 55 00 7E 8A 42 00 00 1E 00 00 00 FD 00 3A

60 3E 1E 53 10 00 0A 20 20 20 20 20 20

70 00

d

c

b

a

MODEL MODEL NAME(HEX)

all 00 00 00 FC 00 4C 47 20 54 56 0A 20 20 20 20 20 20 20

MODEL NAME HEX EDID Table DDC Function

FHD Model 0001 01 00 Analog/Digital

012 3 4 5 6 7 8 9 A BCD EF

00 00 FF FF FF FF FF FF 00 1E 6D 01 01 01 01

10 01 03 80 73 41 78 0A CF 74 A3 57 4C B0 23

20 09 48 4C A1 08 00 81 80 61 40 45 40 31 40 01 01

30 01 01 01 01 01 01 02 3A 80 18 71 38 2D 40 58 2C

40 45 00 7E 8A 42 00 00 1E 01 1D 00 72 51 D0 1E 20

50 6E 28 55 00 7E 8A 42 00 00 1E 00 00 00 FD 00 3A

60 3E 1E 53 10 00 0A 20 20 20 20 20 20

70 01

80 02 03 26 F1 4E 10 1F 84 13 05 14 03 02 12 20 21

90 22 15 01 26 15 07 50 09 57 07

A0 E3 05 03 01 01 1D 80 18 71 1C 16 20 58 2C

B0 25 00 7E 8A 42 00 00 9E 01 1D 00 80 51 D0 0C 20

C0 40 80 35 00 7E 8A 42 00 00 1E 02 3A 80 18 71 38

D0 2D 40 58 2C 45 00 7E 8A 42 00 00 1E 66 21 50 B0

E0 51 00 1B 30 40 70 36 00 7E 8A 42 00 00 1E 00 00

F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

d

e

d

c

b

a

INPUT MODEL NAME(HEX)

HDMI1 67030C001000B82D

HDMI2 67030C002000B82D

HDMI3 67030C003000B82D

HDMI4 67030C004000B82D

D-sub to D-sub DVI-D to HDMI or HDMI to HDMI

For HDMI EDIDFor Analog EDID

Item

Manufacturer ID

Version

Revision

Condition

GSM

Digital : 1

Digital : 3

Data(Hex)

1E6D

01

03

MODEL NAME HEX EDID Table DDC Function

FHD Model 0001 01 00 Analog/Digital

MODEL MODEL NAME(HEX)

all 00 00 00 FC 00 4C 47 20 54 56 0A 20 20 20 20 20 20 20

4.5 Checking the function of Bluetooth using adjusts Remote control

1) Auto checking

• Auto checking is doing in “Power Only”

• Checking the result of searched (check that is in list or not)

• Go out of checking mode pushing button “Exit”

2) Manual checking

• Push the button “Power Only”and “Exit”

• Push the button hot key “Bluetooth “

• Checking the result of searched (check that is in list or not)

• Go out of checking mode pushing button “Exit

4.6 Checking the function of Local Dimming using adjusts Remote control

• Dimming checking is doing in “Power Only”

• Enter the signal of component (Pattern: 7 (combination) , Time :

225 (1920 *1080))

• Push the button “Tilt”

• checking the function of Dimming refer to the Picture at below

• Push the button “Exit”

Patter 7 (combination)

Local Dimming Demo screen

4.7 Outgoing condition Configuration

· 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

Only for training and service purposes

- 17 -

Only for training and service purposes

- 18 -

BLOCK DIAGRAM

Digital Audio (Optic)

RS-232C (Ctrl./SVC)

MAX3232

RS232 IC

+/-

Component 1

Y Pb Pr

Audio L/R

Phone (for RGB)

SPDI

F

RX/TX RX/TX

Serial In

clk, Sync, Va

CVBS

RGB/H/V

EEPROM

AV 1

AV 2

RGB

Audio L/R

USB2.0

USB DP/DM

MIC2019

O.C. Protector

+5V+5V

Side

Rear

DDR2 (1Gbit)

Qimonda / Hynix

NAND Flash

(512Mbit)

Digital AMP

NTP3100L

I2S

DDR_Data[0:15], DQS, DM …

Addr.[ ], ctrl. data

Saturn6

LGE3369A

Data [0 … 7]

Addr[0…1], CS …

SCL, SDA_3.3V

LCD Module

(HD/FHD)

Serial Flash

(32Mbit)

SPI

EEPROM

(512K)

CM3212

Sensor

SCL, SDA_3.3V

DDR2 (256Mbit)

Qimonda / Hynix

DDR_Data[0:15], DQS, DM …

Addr.[ ], ctrl. data

Audio L/R

DivX

HDMI 1

HDMI 2

HDMI 3

5V_HDMI1, HPD1, DDC SCL/SDA, CLK,

DATA

LNA

RF Jack (Digital)

RF Jack (Analog)

XC5000

Tuner

Buffer

CE6355

Demod

LGE7329A

FRC

Component 2

Y Pb Pr

Audio L/R

TX, Clock

Data [0 … 15]

DD [0…15]

HDMI 4

5V_HDMI3, HPD3, DDC SCL/SDA, CLK,

DATA

Side

Rear

DDR2 (256Mbit)

Qimonda / Hynix

DDR2 (512Mbit)

Qimonda / Hynix

DDR_Data[0:15], DQS, DM …

Addr.[ ], ctrl. data

RF S/W

TMDS351

HDMI S/W

DATA, Clock

Select

LG511O

Local Dimming

Data [0 … 15]

ADD [0…15]

clock

- 19 -

Only for training and service purposes

300

200T

200

200N

121

120

510

500

560

810

805

540

804

803

530

801

806

550

820

520

400

802

900

A2

LV1

A10

570

320

EXPLODED VIEW

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the Schematic Diagram and EXPLODED VIEW. It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent X-RADIATION, Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer.

IMPORTANT SAFETY NOTICE

LGE Internal Use Only

Contents of LCD TV Standard Repair Process

LGE Internal Use Only

No. Error symptom (High category) Error symptom (Mid category) Page Remarks

1 2 No video/No audio 2 3 Picture broken/ Freezing 3 4 Color error 4

5

6

7

8

9 Wrecked audio/discontinuation/noise 9 10 11 External device recognition error 11

A. Video error

B. Power error

C. Audio error

D. Function error

No video/Normal audio 1

Vertical/Horizontal bar, residual image, light spot, external device color error

No power 6 Off when on, off while viewing, power auto

on/off No audio/Normal video 8

Remote control & Local switch checking 10

5

7

12 E. Noise Circuit noise, mechanical noise 12 13 F. Exterior error Exterior defect 13

Standard Repair Process

LGE Internal Use Only

LCD TV

Error

symptom

A. Video error

No video/ Normal audio

Established

date

Revised date

2008. 3 .26

First of all, Check whether all of cables between board is inserted properly or not.

(Main B/D↔ Power B/D, LVDS Cable,Speaker Cable,IR B/D Cable,,,)

No video Normal audio

Normal

audio

N

Move to No video/No audio

Y

Check Back Light On with naked eye

Check Power Board 20V or 24v output

On

Normal voltage

Repair Power Board or parts

Y

Check Power Board 12v,5v etc.

N

Replace Inverter

Y

or module

N

Normal

voltage

Repair Power Board or parts

Y

OR

N

End

Electronics 6-3

1/13

Replace Main Board

Replace T-con Board or module

※Precaution

Always check & record S/W Version and White Balance value before replacing the Main Board

Replace Main Board

1

Re-enter White Balance value

Standard Repair Process

LGE Internal Use Only

LCD TV

symptom

No Video/ No audio

Error

Check various voltages of Power Board ( 5V,12V,20V or 24V…)

A. Video error

No video/ No audio

Normal

voltage?

Replace Power Board and repair parts

Y

N

Check and replace MAIN B/D

Established

date

Revised date

End

2008. 3 .26

Electronics 6-3

2/13

2

Standard Repair Process

LGE Internal Use Only

LCD TV

Check RF Signal level

Normal Signal?

N

Check RF Cable

Connection

1. Reconnection

Y

Error

symptom

A. Picture Problem

Picture broken/ Freezing

. By using Digital signal level meter . By using Diagnostics menu on OSD

( Menu→Setup→Diagnostic)

- Signal strength (Normal : over 50%)

- Signal Quality (Normal: over 50%)

Check whether other equipments have problem or not.

(By connecting RF Cable at other equipment)

→ DVD Player ,Set-Top-Box, Different maker TV etc`

Normal

Picture?

Y

Check

S/W Version

SVC

Bulletin?

Established

date

Revised date

2008. 3 .26

■ Menu→Setup →Booster

N

Normal

Picture?

Electronics 6-3

3/13

Y

Close

Normal

Picture?

Y

Close

N

Contact with signal distributor

or broadcaster (Cable or Air)

3

Y

S/W Upgrade

Normal

Picture?

Y

Close

N

Check

Tuner soldering

Replace

Main B/D

Standard Repair Process

LGE Internal Use Only

LCD TV

Check color by input

-External Input

-COMPONENT

-RGB

-HDMI/DVI

Check Test pattern

Error

symptom

Color

error?

N

Check error color input mode

A. Video error

※ Check and replace

Y

Link Cable (LVDS) and contact condition

External Input/

Component

error

Color error

Color

error?

N

Check external device and cable

Y

Replace Main B/D

Established

date

Revised date

External device

/Cable

normal

N

Color

error?

End

Y

2008. 3 .26

Y

Replace T-Con Board

N

Replace Main B/D

Electronics 6-3

4/13

Other Module

Replace module

Y

Color

error?

N

RGB/

HDMI/DVI

error

Check external device and cable

4

Request repair

for external

device/cable

N

External device

/Cable

normal

Y

Replace Main B/D

Standard Repair Process

LGE Internal Use Only

A. Video error

LCD TV

Error

symptom

Vertical / Horizontal bar, residual image, light spot, external device color error

Vertical/Horizontal bar, residual image, light spot

Check color condition by input

-External Input

-Component

-RGB

-HDMI/DVI

Check Test pattern

Screen

normal?

N

Replace module

Check external

Y

device connection condition

Normal?

N

Request repair for external device

External device screen error-Color error

Check screen condition by

Check S/W Version

Check

version

Y

S/W Upgrade

Normal

screen?

Y

End

N

input

-External Input

-Component

-RGB

-HDMI/DVI

Check and

Y

replace Link Cable

External

Input error

Component

error

RGB

error

HDMI/

DVI

5

Established

date

2008. 3 .26

Revised date

Replace T-Con Board

Screen

normal?

End

N

Replace Main B/D

Y

Connect other external device and cable

(Check normal operation of External Input, Component, RGB and HDMI/DVI by connecting Jig, pattern Generator ,Set-top Box etc.

Connect other external device and cable

(Check normal operation of External Input, Component, RGB and HDMI/DVI by connecting Jig, pattern Generator ,Set-top Box etc.

Electronics 6-3

5/13

Other Module

Replace Module

N

Screen

normal?

Y

End

Replace module in abnormal displaying after exchanging T-Con B'd

Screen

normal?

Request repair for external device

Screen

normal?

N

Replace Main B/D

Y

N

Replace Main B/D

Standard Repair Process

LGE Internal Use Only

LCD TV

Check Power LED

. Stand-By: Red . Operating: Blue

Error

symptom

Power LED

On?

N

Check Power cord was inserted properly

Check & Repair

※

Y

Mechanical Power switch

on Local control of TV

Normal?

N

B. Power error

Check ST-BY 5V

No power

DC Power on by pressing Power Key On Remote control

Y

Normal

Y

voltage?

Established

date

2008. 3 .26

Revised date

Normal

operation?

Measure voltage of each output of Power B/D

Normal

voltage?

N

Check Power On ‘”High”

Y

Replace Main B/D

Y

N

Replace Main B/D

OK?

Electronics 6-3

6/13

Replace

Y

Power B/D

N

Y

Close

Replace Power B/D

N

Replace Power B/D

※ ’09 years new model apply mechanical power switch

to reduce power consumption in stand-by status.

If mechanical power switch off

→ Doesn’t turn on by remote control → Doesn’t appear LED light

Please refer to the A21 Page

6

Standard Repair Process

LGE Internal Use Only

LCD TV

Check outlet

Check A/C code

Check for 3 wave length

Error

symptom

Error?

Y

Fix A/C code & Outlet and describe 3 wave length

B. Power error

Off when on, off while viewing, power auto on/off

N

Check Power Off Mode

(If Power Off mode is not displayed) Check Power B/D voltage

※ Caution

Check and fix exterior of Power B/D Part

Abnormal

Established

date

Revised date

CPU

1

Normal

voltage?

Replace Power B/D

Y

N

2008. 3 .26

Replace Main B/D

Electronics 6-3

7/13

Normal?

Replace Power B/D

Y

N

End

* Please refer to the all cases which

can be displayed on power off mode.

Status Power off List Explanation

"POWEROFF_REMOTEKEY" Power off by REMOTE CONTROL "POWEROFF_OFFTIMER" Power off by OFF TIMER "POWEROFF_SLEEPTIMER" Po wer off by SLEEP TIMER "POWEROFF_INSTOP" Power off by INSTOP KEY "POWEROFF_AUTOOFF" Power off by AUTO OFF

Normal

Abnormal

"POWEROFF_ONTIMER" Power off by ON TIMER "POWEROFF_RS232C" Power off by RS232C "POWEROFF_RESREC" Power off by Reservated Record "POWEROFF_RECEND" Power off by End of Recording "POWEROFF_SWDOWN" Power off by S/W Download "POWEROFF_UNKNOWN" Power off by unknown status except listed case

"POWEROFF_ABNORMAL1" Power off by abnormal status except CPU trouble "POWEROFF_CPUABNORMAL" Power off by CPU Abnormal

7

Standard Repair Process

LGE Internal Use Only

LCD TV

No audio

Screen normal

Error

symptom

Check user menu > Speaker off

C. Audio error

No audio/ Normal video

N

Off

Y

Cancel OFF and describe

Check audio B+ 20V or 24V of Power Board

Replace Power Board and repair parts

Established

date

Revised date

Normal voltage

Y

N

2008. 3 .26

Electronics 6-3

8/13

Check Speaker disconnection

Disconnection

Y

Replace Speaker

8

N

Replace MAIN Board End

Standard Repair Process

LGE Internal Use Only

LCD TV

Check input signal

-RF

-External Input signal

Error

symptom

C. Audio error

Wrecked audio/ discontinuation/noise

Established

date

Revised date

2008. 3 .26

Electronics 6-3

→ Wrecked audio/di sco n tinuation/noise i s same after “Check input signal” compared to No audio

Signal

normal?

Y

N

(When RF signal is not received) Request repair to external cable/ANT provider

(In case of External Input signal error) Check and fix external device

Wrecked audio/

Discontinuation/

Noise for

all audio

Wrecked audio/

Discontinuation/

Noise only

for D-TV

Wrecked audio/

Discontinuation/

Noise only

for Analog

Wrecked audio/

Discontinuation/

Noise only

for External Input

Check and replace speaker and connector

Replace Main B/D

Connect and check other external device

Check audio B+ Voltage (20V or 24V)

Normal

voltage?

N

Replace Power B/D

Replace Main B/D

Normal

audio?

Y

N

Y

9/13

End

Check and fix external device

9

Standard Repair Process

LGE Internal Use Only

D. General Function Problem

Remote control & Local switch checking

LCD TV

Error

symptom

1. Remote control(R/C) operating error

Check R/C itself

Operation

Check R/C Operating

When turn off light

in room

If R/C operate,

Explain the customer

cause is interference

from light in room.

operating?

Normal

Y

N

Check & Replace

Baterry of R/C

Normal

operating?

Replace R/C

Check & Repair Cable connection Connector solder

Close

N

Normal

operating?

Y

Close

N

Check B+ 5V

On Main B/D

Established

date

Revised date

Normal

Voltage?

Check 5v on Power B/D

Replace Power B/D or

Replace Main B/D

(Power B/D don’t have problem)

Y

N

2008. 3 .26

Check IR

Output signal

Electronics 6-3

10/13

Replace

Main B/D

Normal

Signal?

N

Repair/Replace

IR B/D

Y

2. Local(Mechanical) switch operating error

Check R/C

Operation

Normal

operating?

N

Move

Power problem

Section

Check & Repair

Y

Cable connection Connector solder

Normal

operating?

Y

Close

Check & Replace

N

Assembly status

(Key PCB + tool )

10

Normal

operating?

Y

Close

N

Check Key

Output signal

Replace

Main B/D

Normal

Signal?

N

Repair/Replace

Local switch B/D

Y

Standard Repair Process

LGE Internal Use Only

LCD TV

Check input signal

Error

symptom

Y

Signal input?

N

Check and fix external device/cable

D. Function error

External device recognition error

Check technical information

- Fix information

- S/W Version

Technical

information?

Fix in

accordance

with technical

information

Established

date

Revised date

External Input and

N

Y

Component

Recognition error

RGB,HDMI/ DVI, Optical

Recognition error

2008. 3 .26

Replace Main B/D

Electronics 6-3

11/13

11

Standard Repair Process

LGE Internal Use Only

LCD TV

Identify nose type

Error

symptom

Circuit

noise

Mechanical

noise

※ Mechanical noise is a natural phenomenon, and apply the 1st level description. When the customer does not agree, apply the process by stage. ※ Describe the basis of the description in “Part related to nose” in the Owner’s Manual.

Check location of noise

Circuit noise, mechanica l noise

E. Noise

Replace inverter

OR

Replace LIPS B/D

Established

date

Revised date

2008. 3 .26

※ When the nose is severe, replace the module (For models with fix information, upgrade the S/W or provide the description)

OR

※ If there is a “Tak Tak” noise from the cabinet, refer to the KMS fix information and then proceed as shown in the solution manual

OR

(For models without any fix information, provide the description)

Electronics 6-3

12/13

12

Standard Repair Process

LGE Internal Use Only

LCD TV

Error

symptom

Zoom part with exterior damage

Module

damage

Cabinet damage

Remote

controller

damage

F. Exterior defect

Exterior defect

Replace module

Replace cabinet

Replace remote controller

Established

date

Revised date

2008. 3 .26

Electronics 6-3

13/13

Stand

dent

Replace stand

13

LCD TV Repair Process Index

LGE Internal Use Only

- Trouble shooting by input block (Component level check)

No. Symptom (L) Input Block Page Remark

1 Power Problem Power-up Boot fail 14 2

No OSD 15 3 Digital TV 16 4 Analog TV 17 5 AV (Scart / CVBS/ S-Video) 18

Video Problem 6 Component 20 7 RGB(D-SUB) 22

8 HDMI 24 9

All Input 26 10 Digital TV 27 11 Analog TV 28

Audio Problem 12 AV / Component / RGB, HDMI-PC/ HDMI-DTV 29 13 No Audio (SPDIF) 35 14 USB / Remocon Problem USB no connect / Remocon 36/37 15 Intelligent Sensor Intelligent Sensor 38

LCD TV

LGE Internal Use Only

Symptom

Power-Up Boot Fail

Making

Revision

2009. 2 . 1 1/25

P800 Pin #7~#10

Voltage Level = 5V ?

NO YES

Check Power connector

OK ?

YES

P800 Pin #2

Voltage level = 5V ?

NO

Replace MAIN B’D Q801

YES

P800 Pin #13, 14 = 12V

P800 Pin #17, 18 = 24V ?

NO

Replace Power Board

YES

MAIN B’D L815 = 3.3V ? Replace MAIN B’D IC804

NO

YES

MAIN B’D L816 = 1.26V ? Replace MAIN B’D IC805

NO

YES

MAIN B’D L809 = 1.8V ? Replace MAIN B’D IC807

NO

Replace Power Board

YES

Check MAIN B’D X100 Clock

12MHz

YES

Replace MAIN B’D IC102

NAND FLASH

NO

Replace MAIN B’D IC100

Replace MAIN B’D IC103

Serial Flash

NO

Replace MAIN B’D

IC300, IC301 DDR2 Memory

14

NO

Replace MAIN B’D IC100

LCD TV

LGE Internal Use Only

Symptom

No OSD

Making

Revision

2009. 2 . 1 2/25

P800 Pin #13, 14 = 12V

P800 Pin #17, 18 = 24V ?

YES

P800 Pin #20

Voltage level = 2V ↑

YES

MAIN B’D L810 = 12V ? Replace MAIN B’D Q805

YES

Check LVDS Cable

OK ?

NO

Replace LVDS Cable

NO YES

NO

YES

Check Power connector

OK ?

Replace MAIN B’D Q802

Replace Main Board

Replace Power Board

15

LCD TV

LGE Internal Use Only

Check RF Cable

YES

Symptom

Digital TV Video Problem

Making

Revision

2009. 2 . 1 3/25

MAIN B’D L1111 = 5V ?

NO

YES

MAIN B’D L1112 = 3.3V ?

NO

YES

MAIN B’D L1113 = 1.8V ? Replace MAIN B’D IC1105

NO

YES

MAIN B’D X1101 Clock ?

NO

Replace MAIN B’D IC808

Replace MAIN B’D IC1103

Replace MAIN B’D X1101

16

LCD TV

LGE Internal Use Only

Check RF Cable

YES

Symptom

Analog TV Video Problem

Making

Revision

2009. 2 . 1 4/25

MAIN B’D L1111 = 5V ?

NO

YES

MAIN B’D L1112 = 3.3V ?

NO

YES

MAIN B’D L1113 = 1.8V ? Replace MAIN B’D IC1105

NO

YES

MAIN B’D X1101 Clock ?

NO

Replace MAIN B’D IC808

Replace MAIN B’D IC1103

Replace MAIN B’D X1101

17

LCD TV

LGE Internal Use Only

Check Signal format

Is it supported?

Check the RCA Cable

YES

Symptom

AV1 (CVBS) No Video

Problem

Making

Revision

2009. 2 . 1 5/25

Check MAIN B’D R420

Video Signal ?

YES

Check MAIN B’D C217

Video Signal ?

YES

Replace MAIN B’D IC 100

NO

MAIN B’D JK402 Check Replace MAIN B’D JK402

NO

Replace

MAIN B’D C217

18

LCD TV

LGE Internal Use Only

Check Signal format

Is it supported?

Check the RCA Cable

YES

Symptom

AV2 (CVBS) No Video

Problem

Making

Revision

2009. 2 . 1 6/25

Check MAIN B’D R465

Video Signal ?

YES

Check MAIN B’D C211

Video Signal ?

YES

Replace MAIN B’D IC 100

NO

MAIN B’D JK402 Check Replace MAIN B’D JK404

NO

Replace

MAIN B’D C211

19

LCD TV

LGE Internal Use Only

Check Signal format

Is it supported?

Check the Component Cable

Symptom

YES

Component1 No Video/ No Color Problem

Making

Revision

2009. 2 . 1 7/25

Check MAIN B’D R421

Video Signal ?

YES

Check MAIN B’D C200, C203 (Y)

C201 (Pb) C202 (Pr)

Video Signal ?

YES

Replace MAIN B’D IC 100

NO

MAIN B’D JK402 Check Replace MAIN B’D JK402

NO

Replace

NO

MAIN B’D C200 or C203 or C201 or C202

20

LCD TV

LGE Internal Use Only

Check Signal format

Is it supported?

Check the Component Cable

Symptom

YES

Component2 No Video/ No Color Problem

Making

Revision

2009. 2 . 1 8/25

Check MAIN B’D R422

Video Signal ?

YES

Check MAIN B’D C214, C209 (Y)

C215 (Pb) C216 (Pr)

Video Signal ?

YES

Replace MAIN B’D IC 100

NO

MAIN B’D JK402 Check Replace MAIN B’D JK402

NO

Replace

NO

MAIN B’D C214 or C209 or C215 or C216

21

LCD TV

LGE Internal Use Only

Check Signal format

Is it supported?

YES

Check the RGB Cable

YES

MAIN B’D JK405 Pin #2

Video signal ? R446 has Vsync ? R447 has Hsync ?

YES

Symptom

NO

RGB No Video Problem

MAIN B’D JK405 Check Replace MAIN B’D JK405

NO

Making

Revision

2009. 2 . 1 9/25

Check MAIN B’D C207 (Video)

R2030 (HSYNC) R2031 (VSYNC)

YES

Replace MAIN B’D IC 100

NO

Replace

MAIN B’D C207 or R2030 or R2031

22

LCD TV

LGE Internal Use Only

Check Signal format

Is it supported?

YES

Check the RGB Cable

YES

MAIN B’D JK405

Pin #3 (BLUE)

Pin #2 (GREEN) Pin #1 (RED)

Video signal ?

YES

Check MAIN B’D C2016 (RED)

C2017 (GREEN)

C2018 (BLUE) Video Signal ?

Symptom

NO

RGB No Color Problem

MAIN B’D JK405 Check Replace MAIN B’D JK405

NO

Replace

NO

MAIN B’D C2016 or C2017 or C2018

Making

Revision

2009. 2 . 1

10/25

YES

Replace MAIN B’D IC 100

23

LCD TV

LGE Internal Use Only

Check Signal format

Is it supported?

YES

Check the HDMI Cable

YES

Symptom

HDMI 1~4 All No Video Problem

Making

Revision

2009. 2 . 1

11/25

Check the ADJUST MENU

EDID OK ?

YES

Replace

MAIN B’D IC601 (HDCP KEY)

NO

Replace MAIN B’D IC 100

Download EDID

(Refer to Adjustment Spec)

NO

24

LCD TV

LGE Internal Use Only

Symptom

Check Signal format

Is it supported?

YES

Check the HDMI Cable

YES

Check MAIN B’D IC600

YES

MAIN B’D JACK Check

JK600 -> HDMI1 JK601 -> HDMI2 JK602 -> HDMI3 JK603 -> HDMI4

HDMI1 or 2 or 3 or 4 No Video Problem

Making

Revision

2009. 2 . 1 12/25

Replace MAIN B’D IC 100

YES

25

LCD TV

LGE Internal Use Only

Symptom

All Source no Audio Problem

Making

Revision

2009. 2 . 1 13/25

Check The Speaker

YES

Check Speaker Cable

YES

MAIN B’D

L824 = 1.8V

YES

MAIN B’D

Check R701, R702, R705

Signal

YES

MAIN B’D L705 Pin #1 L704 Pin #2

PWM Signal ?

NO

Replace Speaker

Replace Speaker Cable

Replace MAIN B’D IC807

Replace MAIN B’D IC100

Check P700 Cable

Replace MAIN B’D IC701

NO

YES

Replace MAIN B’D IC 701

26

LCD TV

LGE Internal Use Only

Digital TV Video OK ?

YES

Replace MAIN B’D IC 100

Symptom

Digital TV No Audio Problem

Making

Revision

2009. 2 . 1 14/25

27

LCD TV

LGE Internal Use Only

Analog TV Video OK ?

YES

Symptom

Analog TV No Audio Problem

Making

Revision

2009. 2 . 1 15/25

Check MAIN B’D

R2046 Signal (SIF)

NO

MAIN B’D

L1101 Signal (SIF)

YES

Replace MAIN B’D IC100

Replace MAIN B’D IC1102

NO

28

LCD TV

LGE Internal Use Only

AV1 Video OK ?

YES

Check the RCA Cable

YES

Check MAIN B’D JK402 Replace MAIN B’D JK402

YES

MAIN B’D

C2011 (Right Sound)

C2012 (Left Sound)

signal ?

Symptom

NO

YES

AV1 No Audio Problem

Replace MAIN B’D IC 100

Making

Revision

2009. 2 . 1 16/25

NO

Check MAIN B’D

C229, C230

29

LCD TV

LGE Internal Use Only

AV2 Video OK ?

YES

Check the RCA Cable

YES

Check MAIN B’D JK402 Replace MAIN B’D JK402

YES

MAIN B’D

C2008 (Right Sound)

C2009 (Left Sound)

signal ?

Symptom

NO

YES

AV2 No Audio Problem

Replace MAIN B’D IC 100

Making

Revision

2009. 2 . 1 17/25

NO

Check MAIN B’D

C2008, C2009

30

LCD TV

LGE Internal Use Only

Component Video OK ?

YES

Check the Component Cable

YES

Symptom

Component1 No Audio Problem

Making

Revision

2009. 2 . 1 18/25

Check MAIN B’D JK402 Replace MAIN B’D JK402

YES

MAIN B’D

C229 (Right Sound)

C230 (Left Sound)

signal ?

NO

Check MAIN B’D

C229, C230

NO

Replace MAIN B’D IC 100

YES

31

LCD TV

LGE Internal Use Only

Component Video OK ?

YES

Check the Component Cable

YES

Symptom

Component2 No Audio Problem

Making

Revision

2009. 2 . 1 19/25

Check MAIN B’D JK402 Replace MAIN B’D JK402

YES

MAIN B’D

C2013 (Right Sound)

C2014 (Left Sound)

signal ?

NO

Check MAIN B’D

C2013, C2014

NO

Replace MAIN B’D IC 100

YES

32

LCD TV

LGE Internal Use Only

RGB Video OK ?

YES

Check the PC Audio Cable

YES

Symptom

RGB, HDMI-PC No Audio Problem

Making

Revision

2009. 2 . 1 20/25

Check MAIN B’D JK401 Replace MAIN B’D JK401

YES

MAIN B’D

C2015 (Right Sound)

C2016 (Left Sound)

signal ?

NO

Check MAIN B’D

C2015, C2016

NO

Replace MAIN B’D IC 100

YES

33

LCD TV

LGE Internal Use Only

HDMI Video OK ?

YES

Symptom

HDMI-DTV No Audio Problem

Making

Revision

2009. 2 . 1 21/25

Check the ADJUST MENU

EDID OK ?

YES

Check the HDMI Cable

Download EDID

(Refer to Adjustment Spec)

NO

Replace MAIN B’D IC100

YES

34

LCD TV

LGE Internal Use Only

Symptom

SPDIF No Audio Problem

Making

Revision

2009. 2 . 1 22/25

Speaker Audio OK

NO

YES

Check the SPDIF Cable

YES

Check MAIN B’D JK403 Replace MAIN B’D JK403

NO

YES

Check MAIN B’D R2305

PWM Signal ?

NO

Replace MAIN B’D IC 100

Check the Trouble Shooting Guide