Haier 20AL25S Schematic

TV-8888-56

SERVICE MANUAL

FOR 20AL25S

TFT-LCD TV

Haier America

Content

CONTENTS -----------------------------------------------------------------------------------------------1
Main Unit Description----------------------------------------------------------------------------------2
Features----------------------------------------------------------------------------------------------------4
Warning and Cautions---------------------------------------------------------------------------------6
Replacement of Memory IC--------------------------------------------------------------------------8
Net Dimension-------------------------------------------------------------------------------------------9
Remote Controller Functions----------------------------------------------------------------------10
ICs function description ----------------------------------------------------------------------------13
Block Diagram------------------------------------------------------------------------------------------21

Trouble Shooting---------------------------------------------------------------------------------------26

Main Unit Description

HLH15BB

2 3 14

67

2 3 14

567

1 2 3 4 5

15HL25S/20AL25S

TV/AV MENU VOL- VOL+ CH- CH+ POWER

5

HLE20BB

7

6

Control Panel Function

1.TV/AV PC/COMPONENT/AV/SV/TV

2. MENU Press to select the main menu

3. VOL-(V-) Volume down / Left orientation to adjust the item in the OSD
VOL+ (V+) Volume up / Right orientation to adjust the item/Press to enter

4. CH-(P-) TV channel down / to select the item in the menu
CH+(P+) TV channel up / to select the item in the menu

5. Power supply switch

6. Power indicator
Illuminates red in standby mode, illuminates green when the display is
turned on

7.Remote Sensor

Selects the input signals:

Receives the signals from the remote control

Connection Options

(The figure is just for referrence, please see actual unit. )

DC Power Cord Socket

This TV operates on DC
power. The voltage is
indicated on the specifications
page. Never attempt to
operate the TV on ac power

DC IN

Pb

COMPONENT IN

Pr Y

D-SUB IN

DVD/DTV Input

Connect a component
device to these jacks

Connect the PC output
connector from a PC to
the audio input port

D-SUB Input

Connect to the VGA
15PIN analog output
connector of the PC
display card for PC
display purpose

AV /S-VIDEO/COMPONENT Audio Input

Connect audio
output from an external
device to these jacks

Antenna Input

Connect cable or
antenna signals to
the TV, either direc­tly or through your
cable box.

R

PC AUDIO IN

L

AUDIO IN

V

VIDEO IN

S-VIDEO

PC Audio Input

Earphone port

S-Video Input

Connect S-Video out
from an S-Video device
to the jacks.

Video Input

Connect video
output from an external
device to this jack

ANT IN

Features

NO.

1
2

3

4
5

6

7

8
9

10

Contrast(Darkroom) 350:1

Response time(ms) 16

NO. of preset channels 100

Model

Functions

TFT LG

Screen size 20inch
Aspect ratio 4:3

Resolution 800*600
Brightness 450cd/m2 cd/m2

Color system NTSC

Picture mode Yes

HLE20BB

11
12

13
14

15
16

17

18
19

20
21

22
23

Angel of view H:176°/ V:176°
Color display 16,777,216

Color level 16

OSD languages ENGLISH,FANCE, SPAISH

Surrounding sound No

Audio system M

Sound mode Yes

AV stereo Yes

Bass Yes

Balance Yes

Mute Yes

BTSC Yes

AV input Yes

24

25
26

27
28

S-video jack NO

AV output NO

Y CB CR Yes
Y PB PR Yes

TV in Yes

Model

NO.

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

Audio output power(Built-in)(W)

Functions

D-SUB jack Yes

DVI socket

SCART socket

Ear-Phone Out

CCD,V-CHIP

Semitransparent menu

ZOOM

16:9 mode

Child Lock

Quick View

NO. of built-in speakers

Total power input（W）

Voltage range（V）

Power frequency（Hz）

Time of sleep timer(MINS)

Approval

Suitable market

20AL25S

NO

NO

Yes

Yes

Yes

NO

NO

NO

Yes

2

2*1.5

40

120

60

240

UL

U.S.

Warnings and Cautions

High voltages are used in the operation of this product.
Do not romove the cabinet back from your set. Refer
servicing to qualified service personnel.

To prevent fire or electrical shock hazard, Do not expose
the main unit to rain or moisture.

Do not drop or push objects into the television cabinet

Warning

Warning

Warning

20c

Minimum
10c

10c

5cm

slots or openings. Never spill any kind of liquid on the
television receiver.

!

Caution

If the television is to be built into a
compartment or similarly enclosed, the
minimum distances must be maintained.
Heat build-up can reduce the service life of
your television, and can also be dangerous.

!

Caution

Never stand on, lean on, push suddenly the product or its
stand. You should pay special attention to children to children.

!

Caution

Do not place the main unit on an unstable cart stand, shelf or
table. Serious injury to an individual, and damage to the
television, may result if it should fall.

!

When the product is not used for an extended period of time, it

Caution

is advisable to disconnect the AC power cord from the AC

outlet.

!

Avoid exposing the main unit to direct sunlight and other
source of the heat. Do not stand the television receiver
directly on other produces which give off heat. E. g. video
cassette players,Audio amplifiers. Do not block the
ventilation holes in the back cover. Ventilation is essential to
prevent failure of electrical component. Do not squash power
supply cord under the main unit.

!

Caution

Caution

The LCD panel used in this product is made of glass.
Therefore, it can break when the prod uct is dropped or
applied with impact. Be careful not to be injured by
broken glass pieces in case the LCD panel breaks.

REPLACEMENT OF MEMORY IC

1. MEMORY IC.

This LCD TV uses memory IC. In the memory IC are memorized data for correctly operating the video and
sound circuits. When replacing memory IC, be sure to use IC written with the initial value of data.

2. PROCEDURE FOR REPLACING MEMORY IC
(1) Power off

Unplug the +12V power plug from +12V power socket.

(2) Replace IC

Be sure to use memory IC written with the initial data values or blank memory IC.

(3) Power On

Plug the +12V power plug into +12V power socket. (If memory IC is blank, the program will take 25s to
initial memory IC.

(4) Check and set SYSTEM default value:

1) Press “DISPLAY” key, then press colour key “red”,”green”,yellow”,”DISPLAY” on the Remote control
unit continuously for factory used.

2) The “Factory2” will be displayed on the screen,

3) Check the setting value of the SYSTEM default value of Table below. If the vale is different, select
items by [CH+]/[CH-] keys and set value by [VOL+]/[VOL-] keys.

4) Press “OK” key and return to the normal screen.

Remote Control Key Functions

When using the remote control, aim it towards the remote sensor on the TV

1 2

MUTE

RECALL DISPLAY EXIT

3 4
5

1 2 3

4 5 6

7 8 9

7 8

9 10

12

13 14
15

MTS/SAP P.STD

MENU TV/AV

VOL

-

CCD SLEEP SCAN

0

CH+

CH-

VOL
+

6

11

Illustration of the keys on the remote control:

1. MUTE

2.

3. RECALL

4. EXIT

5. DISPLAY

6. 0-9

7. MTS/SAP

8. P.STD

9. MENU

10. TV/AV

11. CH+/CH-

12. VOL+

VOL-

MUTE

Power supply switch

Quick TV channel switch(return to the last channel)

Menu exit

Display current input signal information

TV channel number select

Select MONO,STEREO, SAP in NTSC system

Select picture mode: PERSONAL/STANDARD/MILD/FRESH

To display/exit the main menu

Select PC/COMPONENT/AV/SV/TV

TV channel up/down or select the item of the menu
Volume up / to select the main menu/ to adjust the item/ to

enter the submenu.
Volume down / to select the main menu/ to adjust the item

13. CCD

14. SCAN

15. SLEEP

Closed caption on/off

Channel scan

TV sleep button

Remote Control

Installing Batteries

1.Slide open the cover of the battery compartment on the back of the remote
control.

2.Load two batteries in the compartment. (plus and minus poles to
respective mark)

3.Replace the cover of the battery compartment.

AAA alkaline

-

+