ViewSonic VT2645-M User manual

Service Manual
ViewSonic VT2645-M
Model No. VS12675
26” LCD TV
(VT2645-M_SM Rev. 1bApr.2010)
ViewSonic®381 Brea Canyon Road, Walnut, California 91789 USA - [phone]

Copyright
Copyright© 2010 by ViewSonic Corporation. All rights reserved. No part of this publication may be
reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or
computer language, in any form or by any means, electronic, mechanical, magnetic, optical, chemical,
manual or otherwise, without the prior written permission of ViewSonic Corporation.
Disclaimer
ViewSonic makes no representations or warranties, either expressed or implied, with respect to the contents
hereof and specifically disclaims any warranty of merchantability or fitness for any particular purpose. Further,
ViewSonic reserves the right to revise this publication and to make changes from time to time in the contents
hereof without obligation of ViewSonic to notify any person of such revision or changes.
Trademarks
Optiquest is a registered trademark of ViewSonic Corporation.
ViewSonic is a registered trademark of ViewSonic Corporation.
All other trademarks used within this document are the property of their respective owners.
Revision History
Revision SM Editing Date ECR Number Description of Changes Editor
1a 12/22/09Initial Release Sophia Kao
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1b04/06/10 Add Factory & Hospitality mode Sophia Kao

UTABLE OF CONTENTS
Item Page
1. Precautions and Safety Notices 3
2. Product Specification 6
3. Function Description 10
4. Block Diagram 16
5. Exploded Diagram and Exploded Parts List 17
6. Disassembly Procedure 20
7. Recommended Spare Parts List 33
8. BIOS /Firmware Update SOP 34
9. Trouble Shooting Flow Chart 57
10. FAQ 61
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1. Precautions and Safety Notices
Safety Instructions
The symbol is intended to alert the user to presence of un-insulated
“Hazardous Voltage” within the product’s enclosure that may be of sufficient
magnitude to constitute a risk of electric shock to persons.
This symbol is intended to alert the user that improper use of the product
may result in product malfunction. The user should pay attention to avoid accidents or
unnecessary problems.
Wet Location
Apparatus shall not be exposed to dripping or splashing and that no objects filled with
liquids, such as vases, shall be placed on the apparatus.
Outdoor Use
WARNING: To reduce the risk of fire or electric shock, do not expose this apparatus
to rain or moisture.
Disconnect Device - The Mains Plug or An Appliance Coupler
The mains plug or an appliance coupler is used as the disconnect device for
disconnection from the mains, the disconnect device shall remain readily operable.
Safety
Operate the TV on 100V and 120V AC only.
Use the AC power cord specified by ViewSonic and suitable for the voltage where you
use it.
The plug is designed, for safety purposes, to fit into the wall outlet only one way.
If you are unable to insert the plug fully into the outlet, contact your dealer.
If any liquid or solid object should fall inside the cabinet, stop operating, unplug the TV
immediately and have it checked by qualified service technician.
If you will not be using the TV for a long time, disconnect the power by pulling the plug
itself. Do not pull on the cord.
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Carrying The TV
To prevent dropping the TV and causing serious injury, you must follow these
guidelines:
Disconnect all cables before carrying the TV.
Carrying the large size TV requires at least two or three people.
When you carry the TV, place your hands as illustrated and hold it securely.
Do not put stress on the LCD panel and the frame around the screen.
When carrying the TV, do not subject it to shocks, vibration, or excessive force.
When lifting or moving the TV, hold it securely from the bottom. Place your palm
directly under the panel.
Installed on the wall
Installed with stand
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Leave at least this space around the set. Do not install the TV set as follows:
Air circulation is blocked.
Broken pieces
Do not throw anything at the TV.
Doing so may break the screen glass and cause serious injury.
If the surface of the TV cracks, unplug the AC power cord before touching the TV.
Otherwise electric shock may result.
Handling of broken glass and liquid crystal leakage
If the LCD panel gets damaged, crystalline liquid leakage may occur, or scattered
broken glass may result.
Do not touch broken glass or crystalline liquid which is toxic, with bare hands as cuts,
poisoning or skin irritation may occur.
Also do not glass fragments or leaked crystalline liquid get into your eyes or mouth.
Should either contacted your eyes or mouth, rinse the contacted area thoroughly with
water and consult your doctor.
Note
This television includes a QAM demodulator, which should allow you to receive
unscrambled digital cable television programming via subscription service to a cable
service provider.
The type of programming and signal provided by your cable service provider will affect
the availability of digital cable television programming in your area.
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2. Product Specification
2.1 Specification
Dimensions (with stand)
Physical(W)x(H)x(D) 657.7mm x 506.5mm x 220mm
Weight 7.3 kg
LCD 26” TFT Active Matrix RGB
Pixel Pitch 0.1405 (H) x 0.4215 (V) mm
Native Resolution 1366 x 768
Display area 575.769mm (H) x 323.712mm (V)
Speaker Output 5W x 2
Warning: Do not set the graphics card in your computer to exceed these refresh rates; doing
so may result in permanent damage to the LCD TV.
2.2 Front View
Item Description
1 Remote Control Receiver Receives IR signals from the remote control.
2 Power LED Indicator Lights up in blue when the TV is turned on. Lights up in orange when the TV
is in standby mode.
3 Power ON/OFF button Turn the power on from standby mode or turn the power off to return to the
standby mode.
4 SOURCE Select input source.
5 MENU Turn OSD menu ON/OFF.
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6 Volume Up Increase sound volume or select a control while in OSD menu.
7 Volume Down Decrease sound volume or or select a control while in OSD menu.
8 CH Up Channel up when source is TV, or adjust a highlighted control while in OSD
menu.
9 CH Down Channel down when source is TV, or adjust a highlighted control while in
OSD menu.
2.3 Rear View
Item Description
1 Power (AC input) Plug-in the supplied AC Power cord and connect to the AC input power
source (110~120V).
2 USB Service Port Service only. Not available for users.
3 HDMI 1 / 2 Connect this port to the HDMI/HDMI-DVI jack of the compatible equipment.
*If you use HDMI-DVI connections, please use PC Audio In for audio input.
4 PC Audio In Connect the PC Audio Out on your computer to the PC Audio In on the rear
of the LCD TV.
5 VGA Signal Input Connect a 15-pin D-sub RGB cable to the RGB output of your computer
and the other end to the RGB input on the rear of the LCD TV.
6 R/L Audio Inputs (YPbPr) Connect to an external device, such as a VCR, STB, or a DVD player.
7 YPbPr Connect to an external device, such as a VCR, STB, or a DVD player.
8 Coaxial Connect to a digital audio receiver supporting the S/PDIF standard, such as
a home theater receiver.
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9 S-Video Input Connect to an external device, such as a VCR, STB, or a DVD player.
10 AV Connect to an external device, such as a VCR, STB, or a DVD player.
11 R/L Audio Input (AV/S-Video) Connect to an external device, such as a VCR, STB, or a DVD player.
12 TV Cable/Antenna Connect to a cable or antenna TV.
2.4 Remote Control
Button Description
1 POWER Press this button to turn the power on from standby mode. Press it again to
return to the standby mode.
2 FAV 1-3 Press to select favorite channels
3 TV Press to direct to TV source when in any other source.
4 HDMI Press to select source to HDMI or VGA mode.
5 YPbPr Press to select source to YPbPr mode.
6 AV Press to select source to AV or S-Video mode.
7 CC Press to turn Closed Caption On/Off
8 MTS Press to activate Multichannel Television Sound, Stereo or Mono.
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9 0~9, - number buttons Press 0~9 and “-” to select a channel.
After you input the channel numbers, press ENTER button to direct to the
channel immediately, or wait for 3 seconds to change automatically.
10 LAST Press to return to previous channel.
11 INFO Press this button to display the current state of the LCD TV.
12 CH Press to change the channels up or down.
13 +VOL- Press to adjust the volume.
14 MUTE Press to turn off the sound. To restore the sound, press this button again, or
press the VOL+ / VOL- button.
15 SOURCE Press to display the INPUT source list and select the source with /buttons.
To confirm the selection, press ENTER.
16 EXIT Press the button to exit the present menu.
17
Press these buttons to navigate the OSD menus.
/is for function select, and is for function adjustment.
18 ENTER Press to confirm the selection in the OSD menu, or to enter the OSD menu you
select.
Pressing ENTER after you input channel numbers will change channels
immediately.
19 GUIDE Press to display the Electronic Program Guide (EPG).
It contains the program information for the channel you’re watching.
20 MENU Press to turn the OSD (On-Screen Display) menu on.
21 SLEEP Press repeatedly to set the off timer.
The function is used to automatically shut off the LCD TV after a preset period of
time passed. There are several times for choice – Off, 15 Min, 30 Min, 45 Min, 60
Min, 75 Min, 90 Min, 105 Min, and 120 Min.
22 PICTURE Press to adjust Picture mode.
23 WIDE Press to select Video Display format.
24 SOUND Press to adjust Sound mode.
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