TCL LCD20VSHN User manual

20’’ LCD TV TCL LCD20VSHN
1
Service
Service
Service
TABLE OF CONTENTS
Description Page Description Page
SAFETY NOTICE
ANY PERSONATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE
CHASSISAND BE AWARE OF THE NECESSARY SAFETY PRECAUTIONS TO BE USED WHEN SERVICING
ELECTRONIC EQUIPMENT CONTAINING HIGH VOLTAGES.
CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING
R FOR TH
UNIT WHEN S
6.1.Main Board……………………..……….……….......24
6.2.Power Board………………………….……….......26
6.3.Tuner Board………….……………….……….......29
6.4.Key Board……………………………….……….......30
6.5.IR Board………………………………………….......30
6.6.Earphone Board………………………..……….......31
7.Block Diagram……….........................................32
8. Schematic Diagram.…...…………..………………...33
8.1 Main Board……….…………….…………….….......33
8.2 Power Board…………...…………….………….......46
8.3 Tuner Board……....…………………….……….......49
9. Exploded View…..………….………………....….......52
10.BOM List……………….…………………………….53
Table Of Contents.......……..............................…........1
Important Safety Notice.......................................……......2
Revision List.…........................................……...... 3
1. General Specification.................................………........4
2. Operating Instructions……...……………….……….......5
2.1.The Use Of Remote Control……..………….…….......5
2.2. To Use the Menu…...…………………….……….......6
2.3. How to Connect…….…………………….………......12
2.4. Front Panel Control Knobs……………….……….....13
3. Input/Output Specification…………....................…....14
4. Mechanical Instructions…………………….................15
5. Repair Flow Chart ……………………….…….…….....18
6. PCB Layout ……….………….………………....….......24

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Important Safety Notice
Proper service and repair is important to the safe, reliable operation of all TCL Company Equipment. The service
procedures recommended by TCL and described in this service manual are effective methods of performing service
operations. Some of these service operations require the use of tools specially designed for the purpose. The
special tools should be used when and as recommended.
It is important to note that this manual contains various CAUTIONS and NOTICES which should be carefully read in
order to minimize the risk of personal injury to service personnel. The possibility exists that improper service
methods may damage the equipment. It is also important to understand that these CAUTIONS and NOTICES ARE
NOT EXHAUSTIVE. AOC could not possibly know, evaluate and advise the service trade of all conceivable ways in
which service might be done or of the possible hazardous consequences of each way. Consequently, TCL has not
undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not
recommended by TCL must first satisfy himself thoroughly that neither his safety nor the safe operation of the
equipment will be jeopardized by the service method selected.
Hereafter throughout this manual, TCL Company will be referred to as TCL.
WARNING
Use of substitute replacement parts, which do not have the same, specified safety characteristics might create
shock, fire, or other hazards.
Under no circumstances should the original design be modified or altered without written permission from TCL. TCL
assumes no liability, express or implied, arising out of any unauthorized modification of design.
Servicer assumes all liability.
FOR PRODUCTS CONTAINING LASER:
DANGER-Invisible laser radiations when open AVOID DIRECT EXPOSURE TO BEAM.
CAUTION-Use of controls or adjustments or performance of procedures other than those specified herein may
result in hazardous radiation exposure.
CAUTION -The use of optical instruments with this product will increase eye hazard.
TO ENSURE THE CONTINUED RELIABILITY OF THIS PRODUCT, USE ONLY ORIGINAL MANUFACTURER'S
REPLACEMENT PARTS, WHICH ARE LISTEDWITH THEIR PART NUMBERS IN THE PARTS LIST SECTION OF
THIS SERVICE MANUAL.
Take care during handling the LCD module with backlight unit
-Must mount the module using mounting holes arranged in four corners.
-Do not press on the panel, edge of the frame strongly or electric shock as this will result in damage to the screen.
-Do not scratch or press on the panel with any sharp objects, such as pencil or pen as this may result in damage to
the panel.
-Protect the module from the ESD as it may damage the electronic circuit (C-MOS).
-Make certain that treatment person’s body is grounded through wristband.
-Do not leave the module in high temperature and in areas of high humidity for a long time.
-Avoid contact with water as it may a short circuit within the module.
-If the surface of panel becomes dirty, please wipe it off with a soft material. (Cleaning with a dirty or rough cloth may
damage the panel.)

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Revision List
Version
Release Date
Revision Instructions
TPV Model
A00
Mar.-16-2007
Initial Release
E206CHNKF8TL2

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1. General Specifications
Function
20" Screen
Resolution (640x480)
Viewing angel (160° H/ 160° V )
LCD Panel
Screen Size
20” TFT-LCD Panel
Aspect Ratio
4: 3
Resolution
640 x480 (VGA)
Display Area (opening) H x V
408mm x 306mm
Pixel Pitch
0.6375mm x 0.6375mm
Display Colors
16.2 million
Contrast Ratio
400:1
Brightness
350 cd/m2
Viewing angel
160° H/ 160°V
Response Time
12ms
Lamp Type/Life
50000 hr
Color Temperature
Cold / Warm/Normal
VGA Function
Input support definition
640*480 /60Hz
Audio input
Mini jack for stereo headphones (3.5ø)
TV Function
TV Standard
NTSC PAL-N PAL-M
Sound System
MST+SAP
Video Input
Video AV
RCA x 1
Audio L/R x 1
S-VIDEO
S-Videox 1
YPbPr
YPbPr x 1
Audio L/R x 1
YPbPr support modes
480i/P,576i/P,720P,1080i
Audio output
Audio output: L / R
Speaker (built-in): Two 2 watt speakers
Headphone Mini-jack for stereo (3.5ø)
OSD Language
English, France,German, Spanish, Portuguese, Traditional Chinese
Table Stand
Yes
Wall Mount
VESA 100 x 100 mm
Power
Power
AC100V-240V, 50/60Hz
Power Consumption
<75W
Panel Tilt
Forwards/Backwards/
Rotation
-4°/ +18° / ± 35°
Environment
Temperature
+ 5 °C ~ +35 °C
storage
- 25 °C ~ + 60 °C
operating
10% ~ 85%
Dimension
W x H x D (with stand)
500 x 498 x 256 (mm)
Net weight
Without accessory
9.84 Kg
Accessory
Remote controller, Batteriesx2, Power cord, User manual, VGA cable, PC audio cable

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2. Operating Instructions
2.1 The Use of Remote Control
MUTE: Temporarily interrupt the
sound or restore it.
DISPLAY: Press this button to
display Channel.
MTS /SAP: Press this key to
activate Multichannel Television
Sound, Stereo, SAP or Mono
sound.
PRE-CH: To display the
previously selected TV channel.
TV/VIDEO: Select your input
source: press repeatedly to
select source.
CAPTION: Press this button to
select Closed Caption mode off,
CC1~4, TXT 1~4.
SWAP: Not Supported.
Size: Not Supported.
POWER: Power on/Off.
0~9/100 Digit buttons: To
select a TV channel.
CH: Pressor to adjust
channel.
VOL: Press + or - to adjust the
volume.
PC: To change to PC input
mode.
SLEEP: To set sleep timer.
PIP: Not Supported.
MENU: Press repeatedly to
display or exit OSD menu.
V-CHIP: Press this button to
setup parental control, active
after child lock OSD manual is
set to ON.
POP: Not Supported.

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MAIN MENU
2.2 To Use the Menus
1. Press the MENU button to display each menu.
2. Use the cursor up/down buttons to select a menu item.
3. Use the cursor left/right buttons to enter a submenu or enable/disable the function.
4. Press the MENU button to exit the menu.
Press the MENU button to enter themain OSD (On Screen Display). Adjust the items including Sound setup, Picture
Setup, Child Lock Setup, Function Setup and TV setup. When the input source is PC or Component mode, only the
Sound Setup, Picture Setup and Function Setup can be selected; shown in the figure below:
When the input source is Video or S-Video mode, the Sound Setup, Picture Setup, Child Lock Setup and Function
Setup can be selected; shown in the figure below:
When the input source is TV mode, the Sound Setup, Picture Setup, Child Lock Setup, Function Setup and TV
Setup can be selected; shown in the figure below:

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Sound Setup (Same as in PC, TV, Video, S-Video and Component modes)
1. The range of adjusting volume is 0-100, bass is : -05~+05, treble is -05~+05
2. The range of adjusting Balance is L40~ R40; when adjusting from 0 to L40, the sound from the right track
fades until silence; when adjusting from 0 to R40, the sound from the left track fades until silence.
3. AVL: you can set it “ON” or “OFF”.
The function is to adjust the input sound automatically. You may enable this function when you notice that the
sound in the two tracks are very different, in order to prevent the bad sound effect resulting from large sound
variation.
4. Select "ON" or "OFF" for Loudness: default setting is off, you may adjust when necessary.
The following menu will appear when selecting continuously:
5. Preset: Designed for different types of sound output, wherein, the Voice, music and theater modes are preset;
you can set Bass, Treble and Equalizer in sound output mode according to your preference.
6. Equalizer: You can select and adjust 100, 300, 1K, 3K and 8K respectively (the figures represent the sound
frequency range).
7. Reset to default: Reset the sound setting to the factory default value.
Picture Setting
When the input source is in PC mode, you can select Brightness, Contrast, Position, Video noise, Sharpness, Auto
Adjust, Info, Color Temp., Red, Green, Blue and Reset to default; shown in the figure below:
1. Brightness and Contrast: The range can be adjusted from 0~100.
2. Position: There are two options, Horizontal and Vertical, which can be adjusted from -50 to +50.
3. Video noise: There are two options, Phase and Clock, which can be adjusted from -50 to +50.

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4. Sharpness: Select from options of Auto, Softest, Soft, Normal, Sharp and Sharpest. You may adjust the above
options according to your preference.
5. Auto Adjust: Automatically adjust PC input to the optimal screen size.
6. Info: Prompt the current size for PC input definition (only the definition that can be shown by this device).
7. Color Temp.: There are four options of Color temperature provided for users - Warm, Normal, Cold and User.
You can select the three Color temperatures of Warm, Normal, and Cold, or manually adjust red, green or blue
in the User setting (you can only adjust red, green and blue in the User setting).
8. Reset to default: It is used to reset the picture settings to the factory default mode.
When the input source is in TV/Video/S-Video mode, you can select Brightness, Contrast, Color, Sharpness, Tint,
Dyn. skin tone, Temperature. And Reset to default respectively; shown in the figure below:
When the input source is in Component mode, you can select Brightness, Contrast, Video noise, Color, Sharpness,
Tint, Temperature, and Reset to default respectively; shown in the figure below:

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1. Brightness and Contrast: The range can be adjusted from 0~100; use Brightness and Contrast options to adjust
the brightness and contrast of picture.
2. Video noise: There are two options, Phase and Clock, which can be adjusted from -50 to +50.
3. Color: The range can be adjusted from 0~100; use this option to adjust the Color saturation of picture.
4. Sharpness: Select from six options of Normal, Softest, Soft, Auto, Sharp and Sharpest. You can adjust the
sharpness of picture using any option above.
5. Tint: The range can be adjusted from R50~G50; use this option to adjust the Color tone of picture.
6. Temperature: There are three options of Color Temp. Provided for users - warm, normal and cold.
7. Reset: It is used to reset the picture settings to the factory default mode.
Function Setup
When the input source is in TV, Video or S-Video mode, you can select Source OSD, Language, Child lock, Sleep
Timer, CC Mode and Reset to default; shown in the figure below:
1. Current Source OSD setting: When OSD is set to ON, the left upper corner of the display will show the input
source or the TV channel number; when OSD is set to OFF, the input source or the TV channel number will
disappear.
2. OSD language setting: There are six language options provided - English, French, Spanish, German,
Portuguese, Traditional Chinese.
3. Child Lock Setup:
(1). Only when the Child Lock is ON, and the Channel lock will be enabled; when the Child Lock Setup is OFF,
and the Channel lock is disabled.
(2). Lock code: V-Chip password can be set up when the code is locked. Enter the 4-digit password which you
choose! The factory default password is 0000.
4. Sleep Timer: Set the sleeping timer and the alert function which indicates the time left.
5. Closed Caption (CC) setting: Select CC1~CC4, TXT1~TXT4 or OFF.
6. Reset: It is used to reset the OSD settings.

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When the input source is in PC or Component mode, you can select Source OSD, Language, Sleep Timer and
Reset to default; shown in the figure below:
Source OSD, Language, Sleep timer and Reset to default options are operated similarly as the above instructions!
Child Lock
When the input source is in TV, Video or S-Video mode, V-Chip level can be set. You can enter the Child Lock
setting only when the Child Lock is ON. When you enter the Child Lock setting, a message on the display will prompt
you to enter password:
You can enter the Child Lock setting to set up the V-Chip level when you enter the correct password:
1. Age: it may be set to Child, Youth, Young adult, Adult, Custom or OFF; when you select Custom, it can be set
according to you preference.
2. MPAARating: Select the movie ratings from low to high (alert) - G, PG, PG-13, R, NC-17, X and off.
3. PG Rating: Shown in the figure below:
The empty box refers to unlocked; the solid box refers to locked.

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TV Setting
The following menu appears only in the TV mode.
1. Channel nr: Shows the current channel number.
2. Tuning mode: Select the mode of Cable\ Broadcast.
3. System standard: NTSC-M, PAL-N, PAL-M.
4. Auto search: Select "Auto Search" to search all signaled channel; when the searching is complete, it stays at the
first channel with signal and all channels that have been located are stored. If you would like to stop "Auto
Search" during the process, simply by pressing the MENU button.
5. Fine tune: NTSC-M, PAL-N, PAL-M is seldom used.
6. AFC can be set to ON or OFF. When it is set to ON, theTV will search the TV signal automatically; when there is
any offset in the signal, it will automatically adjust the channel to the correct position.
7. Skip can be set to ON or OFF. When it is set to ON, a channel can be skipped when pressing the CH button on
the remote control or on the front panel.
8. Lock can be set to on or off, when it is set to on, the current channel is locked.
9. Reset to default: Reset to the factory default value.

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2.3 How to Connect
Remove the back plate at the back of the TV as shown on the illustration opposite. Lay the LCD TV with the screen
down on a table, as it will be easier to connect your peripheral equipment. Please take precaution not to damage the
screen.
1: VGA audio input
2: VGA input
3: AC power input terminal
4: Headphone outlet
5: AV signal input
6: AV or S-Video left audio track input
7: AV or S-Video right audio track input
8: S-Video signal input
9, 10 and 11: Pr Pb Y Component signal input
12: Y Pb Pr left audio track input
13: Y Pb Pr right audio track input
14: TV signal input
VGA: Receive the signals from computer or video source that has VGA output.
AV: Receive thevideo/audio signals of the NTSC, PAL/N, PAL/M standards.
S-VIDEO(S-VHS): i.e. video Y/C component. Receive the HD Y/C component signal.
Y Pb Pr :The modes it supports are HD signals such as 480i, 480p, 576p and 576i, 720p,1080i
TV: Receive the TV signals of NTSC-M, PAL/N, PAL/M standard.

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2.4 Front Panel Control Knobs
Power Key⑦: Press to turn on or off the TV.
MENU Key⑥: Press to show the OSD menu and exit OSD menu at the TV.
CH Down / Up Key⑤④:Select the intended function by pressing these two keys, or switch the channels in the TV
mode.
Vol + /- Key②③: Press to confirm your function selection and adjustment volume.
Source Key①: Press to select your input source.

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3. Input/Output Specification
3.1 RGB Input Signal Timing
3.2 Connectors
AC Power
: Bottom side
VGA
: Bottom side
: 15-pin D-sub female for ISP
S-Video
: Rear side
: 4 Pin Mini-DIN female
AV (Composite Video)
: Rear side
: RCA female (Yellow)
Component video (Y/Pr/Pb)
: Rear side
: RCA female (Red/Green/Blue)
AV/HD Audio
: Rear side
: RCA female (Red/White)
Video Mode
fH
(kHz)
fV
(Hz)
Dot
clock
(MHz)
Sync
polarity
Horizontal (dot)
H/V
H-total
H-wide
H
Back porch
H Front porch
VESA
VGA 640x480
31.469
59.940
25.175
N
800
96
48
16
Vertical (line)
Analog
V-total
V-wide
H Back porch
H Front porch
526
2
33
11
Y

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4. Mechanical Instructions
1). Remove the hinge cover and cable cover.
Figure 1
2). Remove the 4 screws to remove the base.
Figure 2
3). Remove the 8 screws to remove the back cover.
Figure 3
Note: Put it to a soft, clean and flat surface.
Hinge over
Cable
Cover

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4). Remove the screws to remove the shield and main frame (from bezel).
Figure 4
5). Remove the screws and connect wire to remove the main board, power board and tuner board from main
frame.
Figure 5
Shield
Main Frame

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6). After above steps, turn main frame (with panel) over, and remove 4 screws to remove the panel from main frame.
Figure 6
7). The panel only.

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5. Repair Flow Chart
5.1 No Power (No LED indicator)
Check power cord
and board interface
NG
Plug in power cord and interface
Check F901, BD901
Replace F901 or BD901
Check the circuit
Check IC901 Q901
Replace IC901 or Q901
Check T901
Replace T901
Check D904, D902
Replace D904, D902
Replace Q903, ZD902,
IC903, IC902
Check Q903, ZD902, IC903 IC902
and relative circuit
Check Q906, IC905 and relative circuit
No Power
OK
NG
OK
NG
OK
NG
OK
NG
OK
NG
OK

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5.2 No Display (LED indicator green)
Check the source
Reset source
Check LVDS cable
NG
Replace LVDS cable
Check 12V power supply
Return to “1”
Check U406
Replace U406
Check panel
Replace panel
Check main board power supply
Check I2C communication
Repair I2C communication relative circuit
No display
OK
NG
OK
NG
OK
OK
NG
OK
NG
OK
NG

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5.3 Can’t start (LED indicator yellow)
NG
Repair the keyboard
Check 5V_SB
Check every chip power supply
Check I2C communication
Check keyboard
Replace I2C communication component
Check oscillistor
Replace oscillistor
Can’t start
OK
OK
NG
NG
OK
NG