Haier LET32H320 User manual

Order No.
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.
Haier Group
©2010 Qingdao Haier Electronics Co., Ltd.
All rights reserved. Unauthorized copying and distribution is a violation of law.
SERVICE MANUAL
Haier
WARNING
TV1107S001V0
MT5310
LET32H320
LET42H320

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Service Manual
Model No.: LET32H320 LET42H320
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...........................................6
1-4-1. Using icons ............................................................................................ 6
Chapter 2. Specification
2-1. Specification list.......................................................................8
2-2 External pictures (four faces)..................................................9
Chapter 3. Disassemble and Assemble
3-1 Remove the Stand................................................................... 11
3-2. Remove the Back Cabinet ..................................................... 11
3-3. Remove the Terminal Bracke ............................................... 11
3-5 Remove the Mainboard...........................................................12
3-7. Remove the Remote Control Board......................................12
Chapter 4. Location of Controls and Components
4-1. Board Location.......................................................................13
4-2. Mainboard ...............................................................................15
4-3. Power Supply Board ..............................................................16
4-4. LCD Panel ...............................................................................17
Chapter 5. Installation Instructions
5-1 External Equipment Connections..........................................20
5-2 CONNECTING YOUR TV .........................................................20

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Chapter 6. Operation Instructions
6-1. Front Panel Controls..............................................................22
6-2 Back Panel Controls ...............................................................22
6-3 Setting Up Your Remote Control ...........................................23
Chapter 7. Electrical Parts
7-1. Circuit Diagram.......................................................................24
7-2 . Wiring Connection Diagram .................................................39
Chapter 8. Measurements and Adjustments
8-1. Service Mode .........................................................................41
8-1-1.How to enter into Service Mode............................................................41
8-1-2.How to exit ............................................................................................41
8-2. Measurements and Adjustments ..........................................41
8-2-1. The Main Menu ....................................................................................41
8-2-2. General Setting ....................................................................................42
8-2-3. EEPROM Setting .................................................................................43
8-2-4. Software UpDate .................................................................................43
Chapter 9. Trouble shooting
9-1. Simple check ..........................................................................44
9-2. Mainboard Failure Check ......................................................45
9-3. Pannel Failure .........................................................................52

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Service Manual
Model No.: LET32H320 LET42H320
Chapter 1. General Information
1-1. Document Information
Document format: Adobe PDF
Author: Zhao Xinjie
Compiler: Bao Qinghong
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
king 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 re, 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

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Model No.: LET32H320 LET42H320
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components commonly are called Electrostatically Sensitive (ES) Devices. The following
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

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Model No.: LET32H320 LET42H320
1. Always unplug the receiver AC power cord from the AC power source before:
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.

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3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. 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.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to
damage ES devices.
6. 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).
7. 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.
8. 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.
1-4. How to Read this Service Manual
1-4-1. Using icons:
Icons are used to attract the attention of the reader to specic 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.

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Service Manual
Model No.: LET32H320 LET42H320
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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Model No.: LET32H320 LET42H320
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Model LET32H320 LET42H320
Screen Size 32" 42"
Aspect Ratio 16:9 16:9
Resolution 1920x1080 1920x1080
Response Time (ms) 8 (GRAY TO GRAY) 8 (GRAY TO GRAY)
Angel of View H:178°, V:178° H:178°, V:178°
Color Display 16.7M 16.7M
No. of Preset Channels 100 100
OSD Language English,France etc. English,France etc.
Color System PAL/SECAM PAL/SECAM
Audio System DK, BG, I, M, L DK, BG, I, M, L
Audio Output Power (Built-in) (W) 8W×2 8W×2
Audio Output Power (outer) (W) No No
Total Power Input (W) 80W 130W
Voltage Range (V) AC150V~240V AC150V~240V
Power Frequency (Hz) 50~60Hz 50~60Hz
Time of Sleep Timer (MINS) 120Min 120Min
Net Weight (KG) 6.8 11.5
Gross Weight (KG) 8.5 14.5
Net Dimension (MM) 782X160X557 1014×280×697
Packaged Dimension (MM) 1000×135×635 1282×185×752
Chapter 2. Specification
2-1. Specification list

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Model No.: LET32H320 LET42H320
2-2 External pictures (four faces)
Front Side
Left Side

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Right Side
Back Side

Chapter 3. Disassemble and Assemble
1. Lay down the TV set .
2. Remove the screw from the stand which is
indicated with circle in the picture above.
3. Remove the stand
3-2. Remove the Back Cabinet
1.Remove the two screws indicated with
circle.
2.Remove all pins around the Cabinet.
3.Carefully raise the Back Cabinet from
bottom.
3-3. Remove the Terminal Bracket
3-1 Remove the Stand
Remove the screws indicated by the red
circles in the picture.
LET32H320
LET42H320
3-4. Remove the Power Supply
Module
Remove the screws indicated by the red
circles in below picture.
LET32H320
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3-7. Remove the Remote Control
Board
1. Remove the one screw indicated with
circle.
2. Remove the Remote Control Board.
3-6. Remove the KEY Board
Remove the Key board indicated by red circles
in below picture.
3-8. Remove the Speaker
Remove the screws indicated by the red
circles in below picture.
Take out the speakers.
3-5 Remove the Mainboard
1. Remove the screws indicated with
circle.
2. Remove the Mainbord and the LED Driver
Board.
LET42H320
LET32H320
LET42H320 LET32H320
LET42H320
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LET32H320 LET42H320

Chapter 4. Location of Controls and Components
4-1. Board Location
LET32H320
No. Parts number Description
A Board DH1HD1E0200M Mainboard(0090804469)
B Board 0094002488 Power Supply Board
C Panel 0094002883DA LCD Panel
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Model No.: LET32H320 LET42H320

LET42H320
No. Parts number Description
A Board DH1GL2E0200M Mainboard(0090728289)
B Board 0094001855A Power Supply Board
C Panel 0094001903DB LCD Panel
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Key Board connector J15
Pin number Signal name
1GND
2 KEY1
3 KEY0
4 3.3VS
4-2. Mainboard
Speaker connector J10
Pin number Signal name
1LOUT+
2 LOUT-
3 ROUT+
4 ROUT-
Mainboard power supply
connector J1
Pin number Signal name
112V
212V
3GND
412V
5GND
6GND
75VS
8ADJ
9GND
10 PW
11 NC
12 ON/OFF
Remote control connector J7
Pin number Signal name
15VS
2IR
3 LED_R
4 LED_G
5 GND
Connector Definition
Eye guide connector J17
Pin number Signal name
13V3
2 GND
3 SCL
4 SDA
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LET32H320 LET42H320
LED light connector J700
Pin number Signal name
1LED_R
2 LED_G
3 GND
Remote control connector CN23
Pin number Signal name
15VS
2IR
3 I/O
4 3D
5 GND
9 SDA
8 SCL
7 GND
6 3.3V

4-3. Power Supply Board
CON1 is the Power cord connector
Connector Definition
4-4. LCD Panel
24V connector CON3
Pin number Signal name
1 +24V
2 +24V
3 +24V
4 +24V
5 +24V
6 GND
7 GND
8 GND
9 GND
10 GND
11 NC
12 BL-ON/OFF
13 E-PWM
14 GND
LET32H320
LET42H320
Mainboard power supply
connector CON2
Pin number Signal name
1 12V
2 12V
3 GND
4 12V
5 GND
6 GND
7 5VS
8 ADJ
9 GND
10 PW
11 NC
12 ON/OFF Connector Definition
LET32H320
LET42H320
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Model No.: LET32H320 LET42H320
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LET32H320
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LET42H320
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Chapter 5. Installation Instructions
5-1 External Equipment Connections
ANTENNA CONNECTION
Connect your aerial to the back of the TV into the ANTENNA IN socket.
IMPROVE YOUR SIGNAL
To improve picture quality in a poor signal area, use a signal amplier (not supplied).
5-2 CONNECTING YOUR TV
Remote Control Batteries
Accessories
User Manual
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Service Manual
Model No.: LET32H320 LET42H320