Kogan LET40T3 User manual

Order No.
LED LCD TV
Model No.
Chassis
This service information is designed for experienced repair technicians only and is not designed for use by the general public.
It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product.
Products powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to service or repair
the product or products dealt with in this service information by anyone else could result in serious injury or death.
Kogan Group
©2009 Qingdao Haier Electronics Co., Ltd.
All rights reserved. Unauthorized copying and distribution is a violation of law.
SERVICE MANUAL
WARNING
TV1101S003V0
MSD209
LET40T3

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CONTENTS
Chapter 1.General Information
1-1. Document Information ....................................................................... 3
1-2. General Guidelines.............................................................................. 3
1-3. Important Notice................................................................................... 3
1-3-1. Follow the regulations and warnings ..................................................... 3
1-3-2. Be careful to the electrical shock........................................................... 3
1-3-3. Electro static discharge (ESD)............................................................... 3
1-3-4. About lead free solder (PbF).................................................................. 4
1-3-5. Use the genewing parts (specied parts) .............................................. 4
1-3-6. Safety check after repairment................................................................ 4
1-3-7. Ordering Spare Parts............................................................................. 6
1-3-8. Photo used in this manual ..................................................................... 6
1-4. How to Read this Service Manual .................................................. 7
1-4-1. Using icons: ........................................................................................... 7
Chapter 2. Specication
2-1. Specication list................................................................................... 8
2-2. External pictures (four faces) .......................................................... 9
Chapter 3. Disassemble and Assemble
3-1. Remove the Stand ............................................................................. 10
3-2. Remove the Power Cord ................................................................ 11
3-3. Remove the Back Cover .................................................................. 11
3-4. Remove the Mainboard................................................................... 11
3-5. Remove the speaker ........................................................................ 11
3-6. Remove the Keypad......................................................................... 12
3-7. Remove the Remote Control Board ........................................... 12
3-8. Remove the Stand backstop......................................................... 12
3-9. Remove the indicator light ............................................................ 12
Chapter 4. Location of Controls and Components
4-1. Board Location ................................................................................... 13
4-2. Main Board .......................................................................................... 13
4-2-1. Function Description:........................................................................... 14
4-2-2. Connector denition............................................................................. 14
4-3. Power Supply Board ......................................................................... 14

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4-3-1. Function description:............................................................................ 14
4-3-2. Connector denition:............................................................................ 14
4-4. LCD Panel ............................................................................................. 15
4-4-1. Function Description: Display the signal.............................................. 16
4-4-2. Connector denition:............................................................................ 16
Chapter 5. Installation Instructions
5-1. External Equipment Connections ................................................ 20
5-2. HDMI Connections............................................................................. 24
Chapter 6. Operation Instructions
6-1. Get to know your TV ......................................................................... 27
6-2. Get to know your remote control ................................................. 28
Chapter 7. Electrical Parts
7-1. Block Diagram..................................................................................... 29
7-2. Circuit Diagram................................................................................... 31
7-3. Wiring Connection Diagram........................................................... 45
Chapter 8. Measurements and Adjustments
8-1. Service Mode ...................................................................................... 46
8-1-1.How to enter into Service Mode............................................................ 46
8-1-2.How to exit............................................................................................ 46
8-2. Measurements and Adjustments.................................................. 46
8-2-1. The Main Menu.................................................................................... 46
8-2-2. Video.................................................................................................... 47
8-2-3. Audio.................................................................................................... 48
8-2-4. Software UpDate ................................................................................. 48
Chapter 9. Trouble shooting
9-1. Simple check ....................................................................................... 49
9-2. Power Supply Board Failure Check. ........................................... 50
9-3. Mainboard Failure Check ............................................................... 51
9-4. Pannel Failure ..................................................................................... 52

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Chapter 1.General Information
1-1. Document Information
Document format: Adobe PDF
Author:
Compiler:
1-2. General Guidelines
When servicing, observe the original lead dress. If a short circuit is found, replace all parts which
have been overheated or damaged by the short circuit.
After servicing, see to it that all the protective devices such as insulation barriers, insulation papers
shields are properly installed.
After servicing, make the following leakage current checks to prevent the customer from being
exposed to shock hazards.
1) Leakage Current Cold Check
2) Leakage Current Hot Check
3) Prevention of Electro Static Discharge (ESD) to Electrostatically Sensitive
1-3. Important Notice
1-3-1. Follow the regulations and warnings
Most important thing is to list up the potential hazard or risk for the service personnel to open
the units and disassemble the units. For example, we need to describe properly how to avoid the
possibility to get electrical shock from the live power supply or charged electrical parts (even the
power is off).
This symbol indicates that high voltage is present inside.It is dangerous to make any
kind of contact with any inside part of this product.
This symbol indicates that there are important operating and maintenance instructions
in the literture accompanying the appliance.
1-3-2. Be careful to the electrical shock
To prevent damage which might result in electric shock or fire, do not expose this TV set to
rain or excessive moisture. This TV must not be exposed to dripping or splashing water, and
objects lled with liquid, such as vases, must not be placed on top of or above the TV.
1-3-3. Electro static discharge (ESD)
Some semiconductor (solid state) devices can be damaged easily by static electricity.
Such components commonly are called Electrostatically Sensitive (ES) Devices. The following

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techniques should be used to help reduce the incidence of component damage caused by
electros static discharge (ESD).
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid-state) devices can be damaged easily by static electricity. Such
components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical
ES devices are integrated circuits and some field-effect transistors and semiconductor "chip"
components. The following techniques should be used to help reduce the ncidence of component
damage caused by static by static electricity.
1. Immediately before handling any semiconductor component or semiconductor-equipped
assembly, drain off any electrostatic charge on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available discharging wrist strap device, which
should be removed to prevent potential shock reasons prior to applying power to the unit under
test.
2. After removing an electrical assembly equipped with ES devices, place the assembly on a
conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of
the assembly.
1-3-4. About lead free solder (PbF)
This product is manufactured using lead-free solder as a part of a movement within the
consumer products industry at large to be environmentally responsible. Lead-free solder must be
used in the servicing and repairing of this product.
1-3-5. Use the genewing parts (specied parts)
Special parts which have purposes of re retardant (resistors), high-quality sound (capacitors),
low noise (resistors), etc. are used.
When replacing any of components, be sure to use only manufacture's specied parts shown in
the parts list.
Safety Component
● Components identied by mark have special characteristics important for safety.
1-3-6. Safety check after repairment
Conrm that the screws, parts and wiring which were removed in order to service are put in the
original positions, or whether there are the positions which are deteriorated around the serviced
places serviced or not. Check the insulation between the antenna terminal or external metal and
the AC cord plug blades. And be sure the safety of that.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power source before:

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a. Removing or reinstalling any component, circuit board module or any other receiver
assembly.
b. Disconnecting or reconnecting any receiver electrical plug or other electrical connection.
c. Connecting a test substitute in parallel with an electrolytic capacitor in the receiver.
CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors
may result in an explosion hazard.
2. Test high voltage only by measuring it with an appropriate high voltage meter or other voltage
measuring device (DVM, FETVOM, etc) equipped with a suitable high voltage probe.
Do not test high voltage by "drawing an arc".
3. Do not spray chemicals on or near this receiver or any of its assemblies.
4. Unless specified otherwise in this service manual, clean electrical contacts only by applying
the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or comparable non-
abrasive applicator; 10% (by volume) Acetone and 90% (by volume) isopropyl alcohol (90%-99%
strength).
CAUTION: This is a ammable mixture.
Unless specied otherwise in this service manual, lubrication of contacts is not required.
Capacitors may result in an explosion hazard.
5. Do not defeat any plug/socket B+ voltage interlocks with which receivers covered by this
service manual might be equipped.
6. Do not apply AC power to this instrument and/or any of its electrical assemblies unless all
solid-state device heat sinks are correctly installed.
7. Always connect the test receiver ground lead to the receiver chassis ground before connecting
the test receiver positive lead.
Always remove the test receiver ground lead last. Capacitors may result in an explosion
hazard.
8. Use with this receiver only the test xtures specied in this service manual.
CAUTION: Do not connect the test xture ground strap to any heat sink in this receiver.
9. Remove the antenna terminal on TV and turn on the TV.
10. Insulation resistance between the cord plug terminals and the eternal exposure metal should
be more than Mohm by using the 500V insulation resistance meter.
11. If the insulation resistance is less than M ohm, the inspection repair should be required.
If you have not the 500V insulation resistance meter, use a Tester. External exposure metal:
Antenna terminal Headphone jack.
12. Use only a grounded-tip soldering iron to solder or unsolder ES devices.

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13. Use only an anti-static type solder removal device. Some solder removal devices not
classied as "anti-static" can generate electrical charges sufcient to damage ES devices.
14. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to
damage ES devices.
15. Do not remove a replacement ES device from its protective package until immediately
before you are ready to install it.
(Most replacement ES devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive material).
16. Immediately before removing the protective material from the leads of a replacement ES
device, touch the protective material to the chassis or circuit assembly into which the device will
be installed.
CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety
precautions.
17. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise
harmless motion such as the brushing together of your clothes fabric or the lifting of your foot
from a carpeted oor can generate static electricity sufcient to damage an ES device.)
1-3-7. Ordering Spare Parts
Please include the following informations when you order parts. (Particularly the Version letter)
1. Model number, serial number and software version
The model number and serial number can be found on the back cover of each product. Software
version can be found in the Spare Parts List.
2. Spare part No. and description
Spare part No. and description can be found in the Spare Parts List.
1-3-8. Photo used in this manual
The illustration and photos used in this Service Manual may not base on the final design of
products, which may differ from your products in some way.

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1-4. How to Read this Service Manual
1-4-1. Using icons:
Icons are used to attract the attention of the reader to specific information. The
meaning of each icon is described in the table below:
Note:
A “note” provides information that is not indispensable, but may nevertheless be
valuable to the reader, such as tips and tricks.
Caution:
A “caution” is used when there is danger that the reader, through incorrect
manipulation, may damage equipment, loose data, get an unexpected result or has to
restart(part of) a procedure.
Warning:
A “warning” is used when there is danger of personal injury.
Reference:
A “reference” guides the reader to other places in this binder or in this manual,
where he/she will nd additional information on a specic topic.

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Chapter 2. Specication
2-1. Specication list
Model LET40T3
Screen size 40 inch
Aspect ratio 16:9
Resolution 1920*1080
Response Time(ms) 6 ms
Angel of view 178
Contrast 5000:1
Brightness 450cd/m2
OSD language English etc.
Color system PAL\SECAM
Audio system BG\DK\I\L
Audio output power(Built-in)(W) 8W*2
Audio output power(outer)(W) No
Total power input(W) 120W
Voltage range(V) 150-240V
Power frequency(Hz) 50/60HZ
Net weight(KG) 18.4
Gross weight(KG) 26
Net dimension(MM) 989*280*689
Packaged dimension(MM) 1360*290*760

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2-2. External pictures (four faces)
Front Side
Left Side

Chapter 3. Disassemble and Assemble
3-1. Remove the Stand
1. Lay down the unit so that back cover faces
upward
2. Remove the Five screws from the back
cover which are indicated with the circles in the
picture above.
3. Remove the stand
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Back Side

3-3. Remove the Back Cover
1. Remove the twenty-two screws indicated
by the red circles in below picture.
2. Then remove the back cover from the
unit.
3-2. Remove the Power Cord
Then remove the power cord.
Remove the screw indicated by the red
circles in below picture.
Then remove the mainboard.
3-4. Remove the Mainboard
Remove the five screws indicated by the red
circles in below picture.
3-5. Remove the speaker
Remove the screw indicated by the red
circles in below picture.
Then remove the speaker.
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Remove the screw indicated by the red
circles in below picture.
3-6. Remove the Keypad
The Keypad is conglutinated with front frame
, just uncover the keypad gently.
Then remove the keypad.
Take out the remote control board.
3-7. Remove the Remote Control
Board
3-9. Remove the indicator light
The indicator light is buckled into the front
frame,remove the clasp indicated by the red
circles in below picture.
Take out the indicator light.
3-8. Remove the Stand backstop
Remove the six screws indicated by the red
circles in below picture.
Take out the stand backstop.
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Chapter 4. Location of Controls and Components
4-1. Board Location
No. Parts number Description
A Board 0094001076AD LCD Panel
B Board 0094001897 Power Board
C Board DC19B0E0400M Mainboard (0090723445)
4-2. Main Board
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CN4
CN8
CNB4
CN27
CNB3
CN5
CN10

4-2-1. Function Description:
Main Board
Process signal which incept from exterior equipment then translate into signal that panel can display.
4-2-2. Connector denition
Main board connector
Speaker connector (CN27)
Pin number Signal name
1 LOUT+
2 LOUT-
3 ROUT-
4 ROUT+
12V/5V Connector (CN10)
Keypad Connector (CNB3)
Pin number Signal name
1 +12V
2 +12V
3 GND
4 +12V
5 GND
6 GND
7 5VSTB
8 /
9 GND
10 PW-ON/OFF
11 PB-ADJUS
12 PB-ON/OFF
Pin number Signal name
1 GND
2 KEY1
3 KEY0
4 3.3VS
Rom connector (CNB4)
Pin number Signal name
1 5VS
2 IR
3 LED-R
4 LED-G
5 GND
4-3. Power Supply Board
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4-3-1. Function description:
To supply power for Mainboard, Panel.
4-3-2. Connector denition:
CN1
Pin number Signal name
1 L
2 R
CN2
Pin number Signal name
1 +12V
2 +12V
3 GND
4 +12V
5 GND
6 GND
7 5VSTB
8E-PEM
9 GND
10 PW-ON/OFF
11 NC
12 PB-ON/OFF
4-4. LCD Panel
CN3
Pin number Signal name
1 24V
2 24V
3 24V
4 24V
5 24V
6 GND
7 GND
8GND
9 GND
10 GND
11 NC
12 BL-ON/OFF
13 STATUS
14 E-PWM
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CN2 CN1

4-4-1. Function Description: Display the signal.
4-4-2. Connector denition:
Pin number Symbol Description
1 12V DC Power Supply
2 12V DC Power Supply
3 12V DC Power Supply
4 12V DC Power Supply
5 12V DC Power Supply
6 NC NC
7 GND Ground
8 GND Ground
9 GND Ground
10 Rx1[0]N 1st ,5th LVDS Signal -
11 Rx1[0]P 1st ,5th LVDS Signal +
12 Rx1[1]N 1st ,5th LVDS Signal -
13 Rx1[1]P 1st ,5th LVDS Signal +
14 Rx1[2]N 1st ,5th LVDS Signal -
15 Rx1[2]P 1st ,5th LVDS Signal +
16 GND Ground
17 Rx1CLK- 1st ,5th LVDS Clock -
18 Rx1CLK+ 1st ,5th LVDS Clock +
19 GND Ground
20 Rx1[3]N 1st ,5th LVDS Signal -
21 Rx1[3]P 1st ,5th LVDS Signal +
22 Rx1[4]N 1st ,5th LVDS Signal -
23 Rx1[4]P 1st ,5th LVDS Signal +
24 GND Ground
CN1 Connector
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Pin number Symbol Description
25 Rx3[0]N 3rd,7th LVDS Signal -
26 Rx3[0]P 3rd,7th LVDS Signal +
27 Rx3[1]N 3rd,7th LVDS Signal -
28 Rx3[1]P 3rd,7th LVDS Signal +
29 Rx3[2]N 3rd,7th LVDS Signal -
30 Rx3[2]P 3rd,7th LVDS Signal +
31 GND Ground
32 Rx3CLK- 3rd,7th LVDS Clock -
33 Rx3CLK+ 3rd,7th LVDS Clock +
34 GND Ground
35 Rx3[3]N 3rd,7th LVDS Signal -
36 Rx3[3]P 3rd,7th LVDS Signal +
37 Rx3[4]N 3rd,7th LVDS Signal -
38 Rx3[4]P 3rd,7th LVDS Signal +
39 GND Ground
40 NC NC
41 NC NC
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Pin number Symbol Description
1 12V DC Power Supply
2 12V DC Power Supply
3 12V DC Power Supply
4 12V DC Power Supply
5 12V DC Power Supply
6 NC NC
7 GND Ground
8 GND Ground
9 GND Ground
10 Rx2[0]N 2nd ,6th LVDS Signal -
11 Rx2[0]P 2nd ,6th LVDS Signal +
12 Rx2[1]N 2nd ,6th LVDS Signal -
13 Rx2[1]P 2nd ,6thLVDS Signal +
14 Rx2[2]N 2nd ,6th LVDS Signal -
15 Rx2[2]P 2nd ,6th LVDS Signal +
16 GND Ground
17 Rx2CLK- 2nd ,6th LVDS Clock -
18 Rx2CLK+ 2nd ,6th LVDS Clock +
19 GND Ground
20 Rx2[3]N 2nd ,6thLVDS Signal -
21 Rx2[3]P 2nd ,6th LVDS Signal +
22 Rx2[4]N 2nd ,6th LVDS Signal -
23 Rx2[4]P 2nd ,6th LVDS Signal +
24 GND Ground
25 Rx4[0]N 4th,8th LVDS Signal -
26 Rx4[0]P 4th,8th LVDS Signal +
27 Rx4[1]N 4th,8th LVDS Signal -
CN2 Connector
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Pin number Symbol Description
28 Rx4[1]P 4th,8thLVDS Signal +
29 Rx4[2]N 4th,8th LVDS Signal -
30 Rx4[2]P 4th,8th LVDS Signal +
31 GND Ground
32 Rx4CLK- 4th,8th LVDS Clock -
33 Rx4CLK+ 4th,8th LVDS Clock +
34 GND Ground
35 Rx4[3]N 4th,8th LVDS Signal -
36 Rx4[3]P 4th,8th LVDS Signal +
37 Rx4[4]N 4th,8th LVDS Signal -
38 Rx4[4]P 4th,8th LVDS Signal +
39 GND Ground
40 NC NC
41 NC NC
42 NC NC
43 NC NC
44 NC NC
45 LVDS_SEL HIGH (3.3V) Normal LVDS Format
LOW (GND) JEIDA LVDS Format
46 NC NC
47 NC NC
48 NC NC
49 NC NC
50 NC NC
51 NC NC
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