AOC L42H931 User manual

42″LCDTV AOC L42H931(P)
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Service
Service
Service
Horizontal Frequency
31.5~67.5KHz
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……………..…….…….……….......33
6.4 Key Board………………………..……..………......34
6.5 IR Board………………………….……..………......34
7.Adjustment……..…………………………................35
8.Block Diagram.……....................................................36
9.Schematic Diagram…..………….......………………...38
9.1 Main Board…………………………………...…......38
9.2 Power Board…………..….….……...…………......48
9.3 Inverter Board…………..….……...………….........53
9.4 Key Board……………….……….…………….........54
9.5 IR Board……...………….……….……………........55
10.Exploded View………………………………….…….56
11. BOM List……………….…….…………….…………..58
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…….………….………....14
3.Input/Output Specification…………....................…....16
4.Mechanical Instructions…………………….................18
5.Repair Flow Chart ……………………….…….…….....21
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 Customer Model TPV Model
A00 Apr.09,2010 Initial Release L42H931
E429MANS4WAENN
E429MANS4WAE5N
E429MANS4WACNN
A01 Oct.12,2.2010 Add new models L42H931P E429MANC4WA4NN
A02 Dec.03,2010 Add new models L42H931
E4292ANS4WE6NN
E4292ANS4WE7NN

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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

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8

9

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2.3 How to Connect

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12

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2.4 Front Panel Control Knobs

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1. HDMI – Conecte la fuente primaria para vídeo digital tal como un reproductor multimedia de DVD. La tira de color
negro en la parte trasera de la TV indica esta conexión.
2. PC/VGA IN (ENTRADA PC/VGA) – Conecte aquí los cables de audio y video de una computadora.
3. ENTRADA DE AV (AV/S-VIDEO) – Conecte la fuente primaria para dispositivos de video compuesto tales como
una videograbadora o una consola de videojuegos. Utilice los conectores blanco y rojo para conectar el audio
externo desde la misma fuente. El señal que está siendo llevado por el cable de Vídeo-S y el conector, y el Vídeo
RCA es el Conector Amarillo.
4. VIDEO COMPONENTE (Y/Pb/Pr con audio L/R) – Conecte aquí la fuente primaria para dispositivos de video
componente como un reproductor de DVD o un decodificador. De izquierda a derecha, utilice rojo para la entrada Pr,
azul para la entrada Pb, verde para la entrada Y, rojo para la entrada de audio derecho (R) y blanco para la entrada
de audio izquierdo (L).
5. TV IN (ENTRADA DE TV) – Conecte a un cable RF para TV.
6. AV OUT(SALIDA AV) – Conecte la SALIDA AV Y ENTRADA AV de la otra TV, el señal de modo TV será
mostrado en la otra TV.

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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 5V
2 Green Video 10 Sync Ground
3 Blue Video 11 Not Used
4 Not Used 12 Serial Data for DDC
5 Ground 13 H-Sync.
6 Red Video Ground 14 V-Sync.
7 Green Video Ground 15 Serial Clock for DDC
8 Blue Video 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×Lines
Vertical Horizontal Sync Polarity Presence Screen Mode
Frequency Frequency Horizontal Vertical Horizontal Vertical Normal Full
(Hz) (KHz) (4:3) (16:9)
720×400 70.1 31.5 NEG POS YES YES YES YES
640×480 59.9 31.5 NEG NEG YES YES YES YES
800x600 60 37.9 POS POS YES YES YES YES
1024x768 60 48.363 NEG NEG YES YES YES YES
1360x768 59.79 47.72 NEG POS YES YES YES YES
1400x900 60 55.93 NEG POS YES YES YES YES
1680x1050 60 65.29 NEG POS YES YES YES YES
1920x1080 60 67.50 NEG POS YES YES YES YES
AV (Composite Video Input)
Video1
Video System NTSC/PAL
Amplitude 1.0 Vpp (including sync)
Impedance 75 ohm terminated
S-Video (Y/C Input)
S-Video2
Video System NTSC/PAL
Y signal amplitude 1.0Vpp (including sync)
C signal amplitude 0.286Vpp
Impedance 75 ohm terminated
Component (Y, Pb/Cb, Pr/Cr Input)
Video3
Video system NTSC/PAL
DTV 480i, 480p, 720p, 1080i
Y signal amplitude 1.0Vpp (including sync )
Pr, (R-Y)/Pb, (B-Y) signal
amplitude 0.7Vpp
Impedance 75 ohm terminated

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4. Mechanical Instructions
1. Remove the screws to remove the stand ass’y.
2. Remove the screws to remove rear cover.

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3. Remove the screws to remove main board, power board and inverter board.
4. Remove the screws to remove bracket and separate bezel and panel.

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5. Remove the screws to remove key board, IR board and speaker.