AOC L26W931 User manual

26″LCDTV AOCL26W931
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Service
Service
Service
Horizontal Frequency
31.5~65KHz
TABLE OF CONTENTS
Description Page Description Page
SAFETY NOTICE
ANY PERSON ATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE CHASSIS
AND 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
6.2 Power Board……..……………….…….……….......30
6.3 Inverter Board…..……………….…….……….......35
6.4 Key Board………………………..……..……….......35
6.5 IR Board………………………….……..……….......36
7. Adjustment……..………………………….................37
8. Block Diagram.…….................................................38
9. Schematic Diagram…..…………....………………...40
9.1 Main Board…………………………………...….......40
9.2 Power Board…..………….….……...………….......50
9.3 Inverter Board.…...……….….……...………….......53
9.4 Key Board……………….……….…………….........54
9.5 IR Board……...………….……….…………….........55
10. Exploded View………………………………….…...56
11. BOM List……………….………………….………….57
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……..……………….…….……….....10
2.4 Front Panel Control Knobs…….………….……….....16
3. Input/Output Specification…………....................…....17
4. Mechanical Instructions…………………….................19
5. Repair Flow Chart ……………………….…….…….....23
6. PCB Layout ………………..…………………....….......28
6.1 Main Board…………..………………...…….…….......28

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Important Safety Notice
Proper service and repair is important to the safe, reliable operation of all AOC Company Equipment. The service
procedures recommended by AOC 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, AOC has not
undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not
recommended by AOC 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, AOC Company will be referred to as AOC.
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 AOC.
AOC 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 LISTED WITH 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 Nov.18,2009 Initial release
E2692ANS4WAENN
E2692ANS4WACNN
A01 Jun.13,2010
Add the new power board
(PCB: 715G2907 1 3)
E269SANS4WAENN
E269SANS4WACNN
A03 Nov.11,2010
Add new models
(power PCB: 715G2907 1 3)
E269MANS4WACNN
E269MANS4WAENN

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1. General Specification

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2. Operating Instructions
2.1 The Use of Remote Control

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2.2 To Use the Menus
1. Press the MENU/EXIT button to display or close the main menu.
2. Use the “”, “v”, “﹤”, “﹥”and “ENTER” to move around to select, adjust or confirm an item in the OSD (On
Screen Display) menu.
Press the MENU/EXIT button to enter the main OSD. Adjust the items including Video menu, Audio menu,
Feature menu, Parental menu, Channel menu and VGA menu. However, some function items in the menus may
only be enabled in the particular source modes.
Channel Menu
The Channel menu in TV mode shows as below.
1. Program No.: Shows the current channel number.
2. Tuning mode: Select the mode of TV signal as Cable or Air.
3. System standard: Can set as NTSC-M, Auto, PAL-M or PAL-N. Advice please do not change this item after auto
search action.
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/EXIT button.
5. Fine tuning: Fine tune the frequency of current channel.
6. AFC: AFC can be set to ON or OFF. Set to ON, the TV will search signal automatically; when there is any offset in
the signal, will automatically adjust the channel to the correct frequency.
7. Skip: Skip can be set to ON or OFF. When it is set to ON, a channel can be skipped by pressing the switching
button on the remote control or on the front panel.
VIDEO MENU
The Video menu in most source modes shows as below. It provides several video adjustment items for user fine
tuning the video display. Only in VGA source mode, the Video menu simply provides Preset, Contrast, Brightness,
Color Temp and Size items.
1. Preset: Designed for different types of video mode. Can select Personal, Standard, Vivid, Movie and ECO mode.
2. Contrast: Video contrast adjustment, can adjust only when Preset is set as Personal. The tuning range is 0 ~
100.
3. Brightness: Video brightness adjustment, can adjust only when Preset is set as Personal. The tuning range is 0
~ 100.

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4. Color: Video color Chroma adjustment, can adjust only when Preset is set as Personal. The tuning range is 0 ~
100.
(Not support in PC and HDMI source mode.)
5. Tint: Video tint adjustment, Can only select with NTSC signal. The tuning range is -50 ~ +50. (Not support in
YPbPr, PC and HDMI source mode.)
6. Sharpness: Video sharpness adjustment, the tuning range is 0 ~ 100.
(Not support in HDMI and PC source mode.)
7. Noise reduction: Designed for different noise reduce effect, user can select off, Low, Normal and High. (Not
support in PC source mode.)
8. Color temp: There are three options of color temperature provided for users - warm, normal and cool.
9. Size: There are various functions provided for zoom in or zoom out. Can select Normal, Zoom1, Zoom2 and
Wide.
AUDIO MENU
The Audio menu in TV mode shows as below. It provides audio adjustment for user to modify the audio setting.
1. Preset: Designed for different types of sound mode. Can select Personal, Music and Speech.
2. Bass: Bass tone adjustment, can adjust only when Preset is set as Personal. The tuning range is -10 ~10.
3. Treble: Treble tone adjustment, can adjust only when Preset is set as Personal. The tuning range is -10~10.
4. Balance: Audio balance adjustment, the tuning range is -10~10.
5. Virtual Surround: It can create the perception that there are many more sources of sound than are actually
present.
6. AVL: Choose On or off to adjust volume to be consistent across programs and channels automatically.
FEATURE MENU
The Feature menu in TV mode shows as below. This menu gives users the most flexibilities to satisfy their generally
demands. According to the various requirements in different source modes, certain features should be hidden
(disable) on the menu. The details footnotes will be described clearly below.
1. Menu language: There are four language options provided - English, French, Spanish and Portuguese.
2. Menu timeout: Adjust the time of menu display.
3. Sleep timer: Function with which you can set a time period after which the TV should turn itself off. You can set it
as off, 15m, 30m, 45m, 60m, 90m and 120m.
4. Super contrast: Enhances the contrast of the color saturation. You can select On (default) or Off.
5. DCR: Dynamic contrast
6. Closed Caption: Select CC channel as On, CC when mute or Off.

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7. Analog Caption: Select Analog Caption as CC1, CC2, CC3, CC4, TT1, TT2, TT3, TT4, Off.
8. Reset all: Reset all OSD setting to default value.
PARENTAL MENU
Parental Control: provide the parental Control (V-chip) function setting. Before entering the Parental Control
sub-menu, user has to key in the password first. Enter the Child Lock item, then the user can modify the restricted
table about MPAA or TV Rating respectively. While exiting the sub-menu, the parental control function is working.
(The default password is: 0 0 0 0.)
Setting the Parental Control level
To set the Parental Control level:
1. Press MENU. The on-screen menu opens with Picture highlighted.
2. Press or to select System, then press ▲or ▼to highlight Parental Control.
3. Press ENTER, enter the password (default password is 0000), then press ▲or ▼to highlight Password setting.
4. Press ENTER, then press to set Child lock to Off.
5. To set the MPAA rating, press ▲or ▼to highlight MPAA rating, then press to select the rating you want to lock.
The rating you locked and all higher ratings will be locked. You can select G, PG, PG-13, R, NC-17, X or Off.
6. To set the PG rating, press ▲or ▼to highlight PG rating, then press . The PG rating screen opens.

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7. Press ▼or ▲to select a rating, then press ENTER to lock or unlock the rating. The rating you locked and all
higher ratings will be locked.
NOTE
If you lock or unlock the A (all) rating, all the ratings (D, L, S, V and FV) are locked or unlocked.
8. To set the Canadian English rating, press ▲or ▼to highlight Can. Englishor, then press to select the rating you
want to lock. The rating you locked and all higher ratings will be locked. You can select E, C, C8+, G, PG, 14+, or
18+.
9. To set the Canadian French rating, press ▲or ▼to highlight Can. French, then press to select the rating you
want to lock. The rating you locked and all higher ratings will be locked. You can select E, G, 8+, 13+, 16+, or 18+.
10. Channel Lock: Select channel lock or not.
11. Video Lock: Select source lock or not.
12. Press MENU/EXIT to close the menu.
Password Set: Change the 4-numeral parental control password. Three steps are required for changing the
password: Enter Old Password -> Enter New Password -> Confirm New Password. Note: This item is only available
in TV, Composite and S-Video source modes. The default password is 『0 0 0 0』.
VGA MENU
This option only shows and is available in VGA mode, which provides several items for the VGA display fine tuning.
1. H.Position: Adjust the horizontal position of the picture. (-50~50)
2. V.Position: Adjust the vertical position of the picture. (-50~50)
3. Clock: Adjust picture clock to reduce Vertical-Line noise. (-50~50)
4. Phase: Adjust Picture Phase to reduce Horizontal-Line noise. (-50~50)
5. Auto Adjust: Adjust the settings automatically.

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2.3 How to Connect
Using Your Antenna or Cable for TV
1. Turn off the TV.
2. Connect the coaxial (RF) connector from your antenna or cable (out-of-the-wall, not from the Cable Box) to the
ANTENNA connector at the rear of the TV
3. Turn on the TV.
4. Select TV using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV, or
pressing the TV button on the Remote Control.
5. Connect the AV OUT and AV IN of the other TV, the signal will display on the other TV.
Using the Antenna or Cable for your VCR
1. Turn off the TV.
2. Connect the “Output to TV”, “RF Out” or “Antenna Out” connector on the rear of your VCR to the ANTENNA
connector at the rear of the TV.
3. Turn on the TV.
4. Select TV using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or directly
by pressing the TV button on the Remote Control.
5. Connect the AV OUT and AV IN of the other TV, the signal will display on the other TV.
Connecting Your TV Set-Top Box
Using HDMI
TV Set-Top Boxes that have a HDMI digital interface should be connected to the HDMI input of the LCD TV for
optimal results.

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Using Component Video
Connecting your TV Set-Top Box (Better):
1. Turn off the TV and TV Set-Top Box.
2. Connect the Pr (red color) connector on your TV Set-Top Box to the corresponding Pr (red color) connector in the
Component group.
3. Connect the Pb (blue color) connector on your TV Set-Top Box to the corresponding Pb (blue color) connector in
the Component group.
4. Connect the Y (green color) connector on your TV Set-Top Box to the corresponding Y (green color) connector in
the Component group.
5. Using an audio cable (red and white connectors), connect the cable to the audio output connectors associated
with the Component output on your TV Set-Top Box and connect the other end to the audio connectors associated
with the Component.
6. Turn on the TV and TV Set-Top Box.
7. Select YPbPr using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or
directly by pressing the COMP button on the Remote Control.
NOTE
Refer to your TV Set-Top Box user manual for more information about the video output requirements of the product
or consult your cable or satellite operator.
Connecting Your Basic Set-Top Box
Using Composite Video
1. Turn off the TV and Set-Top Box.
2. Using an AV Cable, connect the Video (yellow color) connector on your Set-Top Box to the corresponding Video
(yellow color) connector in the AV group at the rear of the TV.
3. Using the red and white connectors, connect the cable to the audio output connectors associated with the Video
output on your Set-Top Box and connect the other end to the audio connectors associated with the AV input at the
rear of the TV.
4. Turn on the TV and Set-Top Box.
5. Select AV-1 using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or
directly by pressing the VIDEO button on the Remote Control.

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Using Coax (RF)
1. Turn off the TV.
2. Using a Coax (RF) cable, connect one end to the TV.
3. Turn on the TV.
4. Select TV using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or directly
by pressing the TV button on the Remote Control.
Connecting Your DVD Player
Using HDMI
DVD players that have a digital interface such as HDMI (High Definition Multimedia Interface) should be connected
to the HDMI input of the LCD TV for optimal results.
Connecting your DVD Player (Best)
1. Turn off the TV and DVD player.
2. Connect a HDMI cable to the HDMI output of your DVD player and the other end to the HDMI Input at the rear of
the TV.
3. Turn on the TV and DVD player.
4. Select HDMI using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or
directly by pressing the HDMI/PC button on the Remote Control.
For DVD Players with DVI:
1. Turn off the TV and DVD player.
2. Using a HDMI-DVI cable, connect the DVI end to your DVD player and the HDMI end to the HDMI Input at the
rear of the TV.
3. Turn on the TV and your DVD player.
4. Select HDMI using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV, or
directly by pressing the HDMI/PC button on the Remote.
NOTE
Refer to your DVD player user manual for more information about the video output requirements of the product.
The DVI to HDMI connection provides video only. Connection to an alternate audio player is required for audio
output.

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Using Component Video
Connecting your DVD Player (Better)
1. Turn off the TV and DVD player.
2. Connect the Pr (red color) connector on your DVD player to the corresponding Pr (red color) connector in the
Component at the rear of the TV.
3. Connect the Pb (blue color) connector on your DVD player to the corresponding Pb (blue color) connector in the
Component group at the rear of the TV.
4. Connect the Y (green color) connector on your DVD player to the corresponding Y (green color) connector in the
Component group at the rear of the TV.
5. Using an audio cable (red and white connectors), connect the cable to the audio output connectors associated
with the Component output on your DVD player and connect the other end to the audio connectors associated with
the Component input at the rear of the TV.
6. Turn on the TV and DVD player.
7. Select Component using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV
or directly by pressing the COMP button on the Remote Control.
NOTE
Refer to your DVD player user manual for more information about the video output requirements of the product.
Using S-Video (AV-2)
Connecting your DVD Player (Good):
1. Turn off the TV and DVD player.
2. Connect the S-Video jack on the rear of your DVD player to the S-Video jack in the AV group on the rear of the
TV.
3. Connect an audio cable (white and red connectors) to the audio output connectors associated with the S-Video
output on your DVD player and connect the other end to the audio connectors associated with the AV input on the
rear of the TV.
4. Turn on the TV and DVD player.
5. Select AV-2 using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV, or
directly by pressing the VIDEO button on the Remote Control.

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Using Composite (AV) Video
Connecting your DVD Player (Good)
1. Turn off the TV and DVD player.
2. Connect the Video (yellow color) connector on your DVD player to the Video (yellow color) connector in the AV
group.
3. Connect the R (red color) and L (white color) audio connectors on your DVD player to the corresponding R (red
color) and L (white color) audio input connectors in the AV group.
4. Turn on the TV and DVD Player.
5. Select AV using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or directly
by pressing the VIDEO button on the Remote Control.
Connecting Your VCR or Video Camera
1. Turn off the TV and VCR or Video Camera.
2. Connect the S-Video jack on the rear of your VCR or Video Camera to the S-Video jack in the AV group on the
rear of the TV.
3. Connect an audio cable (white and red connectors) cable to the audio output connectors associated with the
S-Video output on your VCR or Video Camera and connect the other end to the audio connectors associated with
the AV input on the rear of the TV.
4. Turn on the TV and VCR or Video Camera.
5. Select AV-2 using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or
directly by pressing the VIDEO button on the Remote Control.
NOTE
Refer to your VCR or Video Camera user manual for more information about the video output requirements of the
product.
Connecting to a PC

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1. Turn off the TV and PC.
2. Connect a 15-pin D-Sub RGB (VGA) cable to the RGB output of your PC and the other end to the VGA input at
the rear of the TV.
3. Connect the Audio Out on your computer to the AUDIO input at the rear of the TV.
4. Turn on the TV and PC.
5. Select VGA using the SOURCE button on the Remote control or the INPUT keypad on the side of the TV or
directly by pressing the HDMI/PC button on the Remote.
NOTE
For the best picture quality when connecting a computer through VGA, set your computer timing mode to native
resolution of panel. Please refer to the PC or graphic card’s user guide for additional information on how to set the
timing mode and the video output requirements of the product.

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2.4 Front Panel Control Knobs

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3. Input/Output Specification
3.1 RGB Signal Input
15 - Pin Color Display Signal Cable
Pin No. Description Pin No. Description
1 Red Video 9 No Pin
2 Green Video 10 Sync Ground
3 Blue Video 11 RXD
4 TXD 12 Serial Data for DDC
5 Ground 13 H-Sync.
6 Red Ground 14 V-Sync.
7 Green Ground 15 Serial Clock for DDC
8 Blue Ground
3.2 HDMI Digital Connector Pin Assignments
Pin No. Description Pin No. Description
1 TMDS Data2+ 2 TMDS Data2 Shield
3 TMDS Data2- 4 TMDS Data1+
5 TMDS Data1 Shield 6 TMDS Data1-
7 TMDS Data0+ 8 TMDS Data0 Shield
9 TMDS Data0- 10 TMDS Clock+
11 TMDS Clock Shield 12 TMDS Clock-
13 CEC 14 Reserved (N.C. on Device)
15 SCL 16 SDA
17 DDC/CEC Ground 18 +5V Power
19 Hot Plug Detect

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3.3 AV/S-Video/Component Video Inputs
3.4 Compatible Mode Table
Dots x Lines
Vertical Horizontal Sync Polarity Presence Screen Mode
Frequency Frequency Horizontal Vertical Horizontal Vertical Full
(Hz) (KHz) (15:9)
720 x 400 70.1 31.5 NEG POS YES YES NO
640 x 480 59.9 31.5 NEG NEG YES YES YES
800 x 600 60.3 37.9 POS POS YES YES YES
800 x 600 56 31.2 POS POS YES YES YES
1024 x 768 60 48.3 NEG NEG YES YES YES
1280 x 720 60 45 POS POS YES YES YES
1280 x 768 60 47.8 NEG POS YES YES YES
1360 x 768 60 65 POS POS YES YES YES
AV (Composite Video Input)
Video1
System NTSC/PAL
Amplitude 1.0Vpp (including sync)
Impedance 75 ohm terminated
S-Video (Y / C Input)
S-Video2
System NTSC/PAL/SECAM
Y signal amplitude 1.0Vpp (including sync)
C signal amplitude 0.286Vpp
Impedance 75 ohm terminated
Component (Y, Pb/Cb, Pr/Cr Input)
Video3
480 I (SDTV) 15.734 K / 60 HZ 720 - 240
480 P (SDTV) 31.469 K / 60 720 - 480
576 I (SDTV) 15.625 K / 50 720 - 288
576 P (SDTV) 31.250 K / 50 720 - 576
1080I /60 (HDTV) 33.750 K / 60 1920 - 1080
1080I /50 (HDTV) 28.125 K / 50 1920 - 1080
720P /60 (HDTV) 45.00 K / 60 1280 - 720
720P /50 (HDTV) 37.50 K / 50 1280 - 720

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4. Mechanical Instructions
1. Remove the screws to remove the stand base.
2. Remove the screws to remove rear cover.

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3. Release connectors and separate bezel and panel.
4. Remove the screws to remove bracket and speaker.