LG 26LG3000 Service Manual

LCD TV

SERVICE MANUAL

CAUTION

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

CHASSIS : LD84A

MODEL : 26LG3000 26LG3000-ZA

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

Internal Use Only

CONTENTS

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

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

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

DOWNLOAD METHOD...................................................................................................................11

ADJUSTMENT INSTRUCTION.......................................................................................................21

TROUBLE SHOOTING ................................................................................................................23

BLOCK DIAGRAM.........................................................................................................................27

EXPLODED VIEW ...............……………………………................................................................... 29

REPLACEMENT PARTS LIST ............................…...............……………………………................ 32

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

Only for training and service purposes

- 3 -

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

IMPORTANT SAFETY NOTICE

0.15uF

SERVICING PRECAUTIONS

ٛ .

SPECIFICATION

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

1. Application range

1.1 This spec sheet is applied all of the 26" LCD TV

1.2 Not included spec and each product spec in this spec sheet apply correspondingly to the following each country standard and requirement of Buyer

2. Specification

Each part is tested as below without special appointment.

2.1 Temperature: 25± 5 °C

2.2 Relative Humidity: 10 to 90%

2.3 Power Voltage: input voltage (90 ~ 264 V，50/60 Hz ± 3 Hz)

* 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 30 minutes prior to the adjustment.

3. General Specification (TV)

No Item Specification

1 Receiving system PAL BG/DK/I: SECAM LL’/DK: DVB-T

2 Input voltage AC 90 ~ 264 V/ 50,60 Hz

3 Market Europe

4 Screen size 26 inch wide

5 Aspect Ratio 16:9

6 LCD Module V260B1-L11 NH CMO

7 Operating Environment Temp: 5 ~ 35 deg Humidity: 10 to 90%

8 Storage Environment Temp:-20 ~ 50 deg Humidity: 10 to 90%

9 Input Signal

10 Power consumption

6. Vertical refresh rate 56 - 75 Hz

7. Horizontal frequency 31 - 75 KHz

D-sub / Composite / S-Video / Component / SCART / HDMI / CI Slot / SPDIF Normal on < 120W ( Depend on screen size ) Standby < 1W at 240Vac mains, RC standby mode. Switch off < 1W at 240Vac mains, RC in-active

4. Optical Feature

26″LCD Module-CMO

5. External Input Format

5-1. RGB Input

2 LED colors Blue/Red for Power on / sleeping / switch off Preset timings are as below

Pixel

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

1. 720*400 31.468 70.08 28.321

2. 640*480

3 800*600

4. 832*624 49.725 74.55 57.283 Macintosh

5 1024*768

31.469

37.684

37.879

46.875

48.363

56.470

60.123

59.94

75.00

60.31

75.00

60.00

70.00

75.029

clock(

MHz)

25.17

31.50

40.00

49.50

65.00

75.00

78.75

Proposed Remarks

VESA

VESA(XGA)

Input 848*480 60Hz, 852*480 60Hz Î 640*480 60Hz Display

Pixel

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

clock(

Proposed Remarks

MHz)

6 1152*864 67.5 75 108 WXGA

7 1280*720 44.78 60 74.5 WXGA 8 1280X768 47.78 59.87 79.5 VESA(WXGA)

9 1360x768 47.72 59.8 84.625 VESA(WXGA)

10 1440*900 55.5 59.90 88.750

WXGA

* RGB-PC EDID DATA

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 00 FF FF FF FF FF FF 00 1E 6D 00 26 40 E2 01 00 10 04 12 01 03 1C 3A 21 78 2A 1F 9C A3 54 42 97 26 20 0F 47 49 A5 6E 00 81 C0 01 01 01 01 01 01 01 01 30 01 01 01 01 01 01 66 21 50 B0 51 00 1B 30 40 70 40 36 00 B8 88 21 00 00 1E 1A 1D 00 80 51 D0 1C 20 50 40 80 35 00 B0 0E 11 00 00 1C 00 00 00 FC 00 32 60 36 4C 47 33 30 30 30 0A 20 20 20 20 00 00 00 FD 70 00 38 4E 1F 50 11 00 0A 20 20 20 20 20 20 00 C0

5-2. HDMI mode

HDMI video input should support timings defined in CEA 861-B Timing requirements

Resolutio

No

n

H-freq(kHz) V-freq.(kHz)

1 640*480 60 SDTV 480P 4:3 2 720*480 15.734 / 15.6 59.94 / 60 27.00 SDTV 480P 4:3 3 720*480 31.469 / 31.5 59.94 / 60 27.00/27.03 SDTV 480P 16:9 4 720*576 15.625 50 27(54) SDTV 576I 4:3 5 720*576 31.25 50 54 SDTV 576P 16:9 6 1280*720 37.500 50 74.25 HDTV 720P 7 1280*720 44.96 / 45 59.94 / 60 74.17/74.25 HDTV 720P

1920*108

8

9

10

11

12

13

14

0

1920*108

0

1920*108

0

1920*108

0

1920*108

0

1920*108

0

1920*108

0

33.72 / 33.75 59.94 / 60

28.125 50.00

26.97 / 27 23.97 / 24

25

33.716 /

33.75

29.976 /

30.00

56.250 50

67.43 / 67.5 59.94 / 60

specification with extended EDID blocks

Pixel

clock(MHz)

Proposed Remarks

74.17/74.25 HDTV 1080I

74.25 HDTV 1080I

74.17/74.25 HDTV 1080P

74.25 HDTV 1080P

148.5 HDTV 1080P

148.35/148.5

HDTV 1080P

0

HDMI is major for video input. It also can support RGB mode on above timing.(Just only rear HDMI) The video mode is first priority. RGB timing is design in. The color temperature value will copy from TV mode, no need to check

Resolution H-freq(kH

No

z)

V-freq.(H

z)

Pixel

clock(MHz)

Proposed Remarks

1. 720*400 31.468 70.08 28.321

2. 640*480

3 800*600

31.469

37.684

37.879

46.875

59.94

75.00

60.31

75.00

25.17

31.50

40.00

49.50

VESA

4. 832*624 49.725 74.55 57.283 Macintosh

5 1024*768

48.363

56.470

60.123

60.00

70.00

75.029

65.00

75.00

78.75

VESA(XGA)

6 1152*864 75 WXGA

7 1280*720 60 WXGA 8 1280X800 75 WXGA 9 1440*900 55.5 59.90 88.750

WXGA

* HDMI EDID DATA

HDMI1 on the Side

Block 0

Input 848*480 60Hz, 852*480 60Hz Î 640*480 60Hz Display

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 00 FF FF FF FF FF FF 00 1E 6D 00 26 01 01 01 01 10 04 12 01 03 80 3A 21 78 2A 1F 9C A3 54 42 97 26 20 0F 47 49 A5 6E 00 81 C0 01 01 01 01 01 01 01 01 30 01 01 01 01 01 01 66 21 50 B0 51 00 1B 30 40 70 40 36 00 B8 88 21 00 00 1E 40 1F 56 1A 51 00 2A 30 50 2C 40 13 04 58 C2 10 00 00 1E 00 00 00 FD 00 38 60 4E 1E 50 11 00 0A 20 20 20 20 20 20 00 00 00 FC 70 00 32 36 4C 47 33 30 30 30 0A 20 20 20 20 01 2A

Block 1

00 02 03 21 F1 4E 81 02 03 15 12 13 04 14 05 20 21 10 22 1F 10 23 15 07 50 83 01 00 00 65 03 0C 00 20 20 00 01 1D 00 BC 52 D0 1E 20 B8 28 55 40 34 CD 31 30 00 00 1E 01 1D 80 18 71 1C 16 20 58 2C 25 00 34 40 CD 31 00 00 9E 01 1D 00 72 51 D0 1E 20 6E 28 55 50 00 34 CD 31 00 00 1E 01 1D 80 D0 72 1C 16 20 10 60 2C 25 80 34 CD 31 00 00 9E 8C 0A D0 90 20 40 31 70 20 0C 40 55 00 34 CD 31 00 00 18 00 00 00 00 F5

HDMI2 on the Rear Cover

Block 0

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 00 FF FF FF FF FF FF 00 1E 6D 00 26 01 01 01 01 10 04 12 01 03 80 3A 21 78 2A 1F 9C A3 54 42 97 26 20 0F 47 49 A5 6E 00 81 C0 01 01 01 01 01 01 01 01 30 01 01 01 01 01 01 66 21 50 B0 51 00 1B 30 40 70 40 36 00 B8 88 21 00 00 1E 40 1F 56 1A 51 00 2A 30 50 2C 40 13 04 58 C2 10 00 00 1E 00 00 00 FD 00 38 60 4E 1E 50 11 00 0A 20 20 20 20 20 20 00 00 00 FC 70 00 32 36 4C 47 33 30 30 30 0A 20 20 20 20 01 2A

Block 1

00 02 03 21 F1 4E 81 02 03 15 12 13 04 14 05 20 21 10 22 1F 10 23 15 07 50 83 01 00 00 65 03 0C 00 10 20 00 01 1D 00 BC 52 D0 1E 20 B8 28 55 40 34 CD 31 30 00 00 1E 01 1D 80 18 71 1C 16 20 58 2C 25 00 34 40 CD 31 00 00 9E 01 1D 00 72 51 D0 1E 20 6E 28 55 50 00 34 CD 31 00 00 1E 01 1D 80 D0 72 1C 16 20 10 60 2C 25 80 34 CD 31 00 00 9E 8C 0A D0 90 20 40 31 70 20 0C 40 55 00 34 CD 31 00 00 18 00 00 00 00 05

6. Mechanical specification

NO. Item Content Unit Remark

1

2 Product

Product

Dimension

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

Before packing TBD TBD TBD mm With Stand

After packing TBD TBD TBD mm Box Out Size

Only Set TBD kg

With Box TBD kg

Download Method

1. How to Enter the Service Menu

1) Turn on the TV set.

2) After displaying, press ‘Menu’ key.

3) Press ‘0’ key (Number key ‘zero’) four times slowly.

4) Showing the Service Menu.

2. F/W Download Method

Please refer to the attached F/W download SOP file: “S/W download SOP”, MTK Tool, S/W.

Connect the serial cable from PC RS232 port to TV RS-232 port.

1) Run the MTK tool (as picture 1), and select “MTK 538*”, “COM 1”.

2) Press the “Browse”, and select the correct S/W. (as picture 2, e.g.L32W981 bin path)

3) Press “Upgrade” to start S/W upgrade. (can’t in PC mode, can’t plug off when upgrade)

4) When it displays 100% finished, it is OK (about 10 minutes). (as picture 3)

5) After download the S/W, press “MENU+1999” to reset the TV.

Picture 1

Picture 2

3. EDID Download Method

1) System Connection

Tool list: 715G2005-C 1PCS

Printer cable 1PCS

12V ADAPTER 1PCS

DVI-HDMI cable 1PCS

VGA cable 1PCS

This system should be connected as shown below

EDID JIG (LGE P/No. : AGF73711301)

Picture 3

P/No. : AGF73711301

This system should be connected as shown below

Note: Do not connect VGA and DVI-HDMI cable with ISP board at the same time

Connect to PC

Connect to TV HDMI port

Connect to

12V

DDC connect for HDMI (DVI-HDMI cable) DDC connect for VGA

2) Preparations

Running Port95nt.exe to install Driver LINK Port I/O Driver, and restart PC. (as picture 4)

TV VGA port

Picture 4

Check the TV model name, find the corresponding EDID date (as picture 5)

Picture 5

Turn on TV, press “menu”+1998 to enter EDID ISP mode. you will see the following menu. And then EDID ISP mode on,

if this menu disappear, EDID ISP mode will turn off automatically.

3) VGA EDID update

① Open the VGA file, and running WinDDC.exe, you will see the following table (e.g.19LG3000)

② Check the connection below is right, and TV should in EDID ISP mode, if the EDID ISP mode menu disappear

please enter it again.

Connect to PC

Connect to

12V

TV VGA port

r

③ Click “Write EDID”, appear the dialog box. Key in correct serial number according to rating label of back cover, and

click “OK” (as picture 6)

Click here

Key in correct serial numbe

Picture 6

④ Appear “write ok” on the screen that indicate you are successful to write.

⑤ Appear “IIC Communication Error” on the screen that indicate fail to write. Please check whether the connection is

OK and whether the EDID ISP mode menu is disappear.

4). HDMI EDID update

Notice: Please write or read the VGA EDID firstly by Winddc.exe

① Open the HDMI file, and running DDC20.exe, you will see the following DOS table. (e.g.19LG3000)

p

r

② Check the connection below is right, and TV should in EDID ISP mode, if the EDID ISP mode menu disappear

please enter it again.

Connect to PC

Connect to TV HDMI port

12V

③ “1” means write. “2” means read. Key in “2” and press “Enter” on keyboard can read the HDMI EDID date of this TV.

Key in “1” and press “Enter” can update HDMI EDID date, key in correct serial number according to rating label of back

cover, and press “Enter” (as picture 7)

Key in correct

Key in “1” and

ress “Enter”

serial numbe

Picture 7

④ If the screen shows “data compare OK”, it means the EDID writing process is OK. Press “Ctrl” + “C” to exit

DOS mode.

⑤ If the screen shows as below, it means the EDID writing process is fail. Please check whether the connection is OK

and whether the EDID ISP mode menu is disappear.

4. Serial Number Download Method

Please refer to the attached Serial number scan file: “Scan serial number SOP” and “LG Serial Number”.

Connect the serial cable from PC RS232 port to TV RS-232 port.

1) Open the program “WBadjust.exe”, press the “Config” option, if serial port displays fail (as picture 8), then you must

check whether Com2 exist. After that press the “Program” option to start scanning serial number process.

2) If adjust successfully, display

; If adjust fail, display .

Picture 8

ADJUSTMENT INSTRUCTION

1. Application Range

This spec. sheet is applied to the models of 19LG3000，22LG3000and 26LG3000

2. Specification.

2.1 Adjustment must be done in the correct sequence.

2.2 The adjustment must be performed at 25±5°C temperature and 10 to 90% relative humidity if there is no specified

designation.

2.3 The input voltage of the receiver must be kept between 90 to 264 V，50/60 Hz ± 3 Hz.

2.4 Before adjustment execute Heat-Run for 30 minutes at RF no signal.

3. ADC Calibration

3.1. ADC Calibration

ADC Component RGB-PC

19LG3000

Timing:314

Pattern:185

22LG3000

720P/50HZ

3.1.1 Prepare

1) Power on the Chorma 22291/23291 and power on the PC.

2)Change TV Source to PC mode。

3) Connect PC Com3 to Chroma 22291/23291 RS-232 connector. Make sure USB-to-Serial Com to Com7.

3.1.2 ADC Picture

3.1.3 ADC Adjust

1)Open the program，press the Config button，if serial Comm open fail, then you must check whether Com3 and Com7

Timing:137

Pattern:42

1024*768/50HZ

are exist。

2)If step one is OK，press the PROGRAM button start adjustment。

3) If adjust successful ,

"ADC" will be green, as 。 If adjust fail ,"ADC" will be red, as 。

3.2. W/B Adjustment

z The color temperature at the screen Should be :

CCT

x

y

Warm Normal Cool

6500k 9300k 11000k

0.314 0.283 0.273

0.324 0.297 0.285

Tolerance ∆x, ∆y = +/- 0.020

Factory alignment tolerance ∆x, ∆y = +/- 0.005

3.2.1 Prepare

1) Power on the Chorma 22291/23291 and power on the PC.

2) Change TV Source to PC mode。

3) Connect PC Com3 to Chroma 22291/23291 RS-232 connector. Make sure USB-to-Serial Com to Com7.

3.2.2 W/B Adjust

1)Open the program，press the Config button，if serial Comm open fail, then you must check whether Com3 and Com7

are exist。

2) Press Connect to CA-210 button, then wait a minute, until connect OK.

3)If step one and step two are OK，press the PROGRAM button start adjustment。

TROUBLE SHOOTING

1. No Power (LED Blank )

No Power

Check power

cord and board

interface

OK

Check F901, BD901

OK

Check Q901

OK

Check IC901

OK

Check T931 Replace T931

CheckQ934, IC932, IC933 and relative circuit

OK

NG

Plug in power cord and

interface

NG

Replace F901 or BD901

NG

Replace Q901

NG

Replace IC901

NG

Replace IC903 IC902

2. No Display

No display

Check the source

OK

Check LVDS cable

OK

Check 12V power supply

OK

Check main board power

OK

NG

Check U404

OK

Check I2C communication

OK

Check panel

NG

3. Can’t start (LED indicator Blank)

Can’t start

Check keyboard

OK

Check 5V_SB

OK

Check I2C communication

OK

Check oscillistor

NG

Replace U404

NG

Replace panel

NG

Reset source

Replace LVDS cable

Return to “1”

Repair I2C communication relative circuit

Repair the keyboard

Check every chip power supply

Replace I2C communication component

NG

Replace oscillistor

4. Abnormal Display

Abnormal display

Check the source

NG

Reset source

AV, S-video signal component PC signal

OK

Repair each relative circuit

OK

Check signal filter circuit

Check input signal

OK

Check LVDS cable

OK

Check panel

NG

Replace the filter or inductance

OK

RF signal

Replace LVDS cable

Replace panel

Check TV system setup

OK

Check TU201

OK

Replace TU201

5. No Sound

A

r

Check Amplifier TDA8932BTW U602

No sound

Check the source

OK

Check signal filter circuit

Check Earphone jack

OK

Check speaker

Reset source

NG

Replace the filter or inductance

NG

Replace the Earphone jack

SIF signal Check TV system setup

OK

Check TU201

V, c o mponent, S-video, PC signal

NG

Replace U602

NG

Replace speake

NG

Replace TU201

Check relative circuit