Sharp LC-20S1M Schematic

LC-20S1M

SERVICE MANUAL

S73F5LC-20S1M

LCD COLOUR TELEVISION

MODEL

In the interests of user-safety (Required by safety regulations in some countries) the set should be restored to its original condition and only parts identical to those specified should be used.

CONTENTS

» IMPORTANT SERVICE SAFETY PRECAUTION ........................................................................................2

» SPECIFICATIONS ........................................................................................................................................4

» OPERATION MANUAL .................................................................................................................................5

» DIMENSIONS ...............................................................................................................................................7

» REMOVING OF MAJOR PARTS ..................................................................................................................8

» ADJUSTING PROCEDURE OF EACH SECTION .....................................................................................12

» TROUBLE SHOOTING TABLE...................................................................................................................18

» CHASSIS LAYOUT .....................................................................................................................................22

» BLOCK DIAGRAM ......................................................................................................................................24

» OVERALL WIRING DIAGRAM ...................................................................................................................26

» DESCRIPTION OF SCHEMATIC DIAGRAM .............................................................................................28

» SCHEMATIC DIAGRAM .............................................................................................................................29

» PRINTED WIRING BOARD ASSEMBLIES................................................................................................52

» REPLACEMENT PARTS LIST....................................................................................................................63

» PACKING OF THE SET ..............................................................................................................................75

LC-20S1M

Page

SHARP CORPORATION

LC-20S1M

IMPORTANT SERVICE SAFETY PRECAUTION

Service work should be performed only by qualified service technicians who are thoroughly familiar with all safety checks and the servicing guidelines which follow:

WARNING

1. For continued safety, no modification of any circuit should be attempted.

2. Disconnect AC power before servicing.

CAUTION: FOR CONTINUED PROTECTION AGAINST A RISK OF FIRE REPLACE ONLY WITH SAME TYPE F3701(2A, 250V), F3301(1.25A, 250V), F6700 (1.25A, 250V), F6701 (1.25A, 250V), F6702 (1.25A, 250V), F6703 (1.25A, 250V) AND F6704 (1.25A, 250V) FUSE.

BEFORE RETURNING THE RECEIVER (Fire & Shock Hazard)

Before returning the receiver to the user, perform the following safety checks:

1. Inspect all lead dress to make certain that leads are not pinched, and check that hardware is not lodged between the chassis and other metal parts in the receiver.

2. Inspect all protective devices such as non-metallic control knobs, insulation materials, cabinet backs, adjustment and compartment covers or shields, isolation resistor-capacitor networks, mechanical insulators, etc.

3. To be sure that no shock hazard exists, check for leakage current in the following manner.

• Plug the AC cord directly into a 110~240 volt A C outlet, and connect the DC power cable into the receiver's DC jack. (Do not use an isolation transformer for this test).

• Using two clip leads, connect a 50k ohm, 10 watt resistor paralleled by a 0.15µF capacitor in series with all exposed metal cabinet parts and a known earth ground, such as electrical conduit or electrical ground connected to an earth ground.

• Use an AC voltmeter ha ving with 5000 ohm per volt, or higher, sensitivity or measure the AC voltage drop across the resistor.

• Connect the resistor connection to all exposed metal parts having a return to the chassis (antenna, metal cabinet, screw heads, knobs and control shafts, escutcheon, etc.) and measure the AC voltage drop across the resistor. All checks must be repeated with the AC cord plug connection reversed. (If necessary, a nonpolarized adaptor plug must be used only for the purpose of completing these checks.) Any reading of 0.75V peak (this corresponds to 0.5 mA. peak AC.) or more is excessive and indicates a potential shock hazard which must be corrected before returning the monitor to the owner.

DVM

AC SCALE

50k ohm

10W

0.15 µF

TEST PROBE

TO EXPOSED METAL PARTS

CONNECT TO KNOWN EARTH GROUND

234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121

SAFETY NOTICE

Many electrical and mechanical parts in LCD television have special safety-related characteristics. These characteristics are often not evident from visual inspection, nor can protection afforded by them be necessarily increased by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in this manual; electrical

and shaded areas in the

Schematic Diagrams.

For continued protection, replacement parts must be identical to those used in the original circuit. The use of a substitute replacement parts which do not have the same safety characteristics as the factory recommended replacement parts shown in this service manual, may create shock, fire or other hazards.

components having such features are identified by “ å”

234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121

Replacement Parts Lists and

LC-20S1M

Precautions for using lead-free solder

1 Employing lead-free solder

"All PWBs" of this model employs lead-free solder. The LF symbol indicates lead-free solder, and is attached on the PWBs and service manuals. The alphabetical character following LF shows the type of lead-free solder. Example:

L Fa

Indicates lead-free solder of tin, silver and copper.

2 Using lead-free wire solder

When fixing the PWB soldered with the lead-free solder, apply lead-free wire solder. Repairing with conventional lead wire solder may cause damage or accident due to cracks. As the melting point of lead-free solder (Sn-Ag-Cu) is higher than the lead wire solder by 40°C, we recommend you to use a dedicated soldering bit, if you are not familiar with how to obtain lead-free wire solder or soldering bit, contact our service station or ser vice branch in your area.

3 Soldering

As the melting point of lead-free solder (Sn-Ag-Cu) is about 220°C which is higher than the conventional lead solder by 40°C, and as it has poor solder wettability, you may be apt to keep the soldering bit in contact with the PWB for extended period of time. However, Since the land may be peeled off or the maximum heat-resistance temperature of parts may be exceeded, remov e the bit from the PWB as soon as you confirm the steady soldering condition. Lead-free solder contains more tin, and the end of the soldering bit may be easily corroded. Make sure to turn on and off the power of the bit as required. If a different type of solder stays on the tip of the soldering bit, it is allo y ed with lead-free solder. Clean the bit after every use of it. When the tip of the soldering bit is blackened during use, file it with steel wool or fine sandpaper.

Be careful when replacing parts with polarity indication on the PWB silk.

Lead-free wire solder for servicing

Part No, ★ Description Code ZHNDAi123250E J φ0.3mm 250g(1roll) BL ZHNDAi126500E J φ0.6mm 500g(1roll) BK ZHNDAi12801KE J φ1.0mm 1kg(1roll) BM

LC-20S1M

SPECIFICATIONS

ITEMS

LCD panel

Number of pixels 921,600 dots Video color systems World multi system

TV Standard (CCIR) I/DK/M/BG TV Tuning System Auto preset tuning

TV function STEREO/BILINGUAL NICAM-BG, I, DK/A2 stereo-BG

AUTO PRESET Yes

CATV S1~S41 ch. Hyper Band 4-LINE DIGITAL COMB FILTER Yes Brightness 430 cd/m Lamp life 60,000 hours Viewing angles H: 170° V: 170° Audio output 2.1 W 2 Speakers

AV1 Composite Video, S-Video, Audio Terminals

OSD LANGUAGE English/Chinese/Arabic Power requirement DC 12 V, AC 110–240 V, 50/60 Hz Weight

Accessories Remote control, Battery ( 2), Antenna cable, AC adapter,

AV2 IN/OUT Composite Video, S-video, Audio IN/Composite Video, Audio OUT

COMPONENT Y, P

Headphone jack 3.5 mm ø jack (Front)

MODEL

LC-20S1M

19.7” (50cm) Advanced Super View & BLACK TFT LCD

4 7 cm, 2 pcs.

, PR/Audio

6.3 kg w/o accessories

AC cord, Cable clamp, Operation manual

As a part of policy of continuous improvement, SHARP reserves the right to make design and specification changes for product improvement without prior notice. The performance specification figures indicated are nominal values of production units. There may be some deviations from these values in individual units.

OPERATION MANUAL

LOCATION OF USERS CONTROL

Main unit (front view)

PRESET

Note:

• TV/VIDEO, CH (

)/(

), VOL (–)/(+), and MENU on the main unit have the same functions as the same buttons

on the remote control. Basically, this operation manual provides a description based on operation with the remote

control.

MAIN POWER

TV/VIDEO

CH (

)/( )

VOL (–)/(+)

Upper control panel

Speaker

* The examples used throughout this manual are based

on the LC-20S1M model.

HEADPHONE jack

Plug the headphone mini-plug into the HEADPHONE

jack located on the front of the TV set.

The screen can be adjusted

backwards to an angle be-

tween 12 degrees and 35

degrees. The screen cannot

be set up straight. When

changing the angle, make sure

to hold the stand and adjust

the screen to the best viewable

angle.

OPC sensor

Remote control sensor

OPC indicator (Optical Picture Control)

The Optical Picture Control indicator lights up green

when the BRIGHTNESS is set to AUTO.

POWER indicator

A green indicator lights when the power is on and a red

indicator lights when in the standby mode (the indicator

will not light when the main power is off).

Adjustable

range

Main unit (rear view)

S-VIDEO

AUDIO (L)

VIDEO

AUDIO (R)

AUDIO (L)

COMPONENT

AUDIO (L)

AUDIO (R)

VIDEO

AV-IN1

Carrying handle

AUDIO (R)

S-VIDEO

ANT. (Antenna terminal)

POWER INPUT

(DC12V)

AV-IN2/OUTAV-OUT

Stand

* Be careful to prevent the

product from falling over

when adjusting the angle.

Also place the product on

a stable base.

The screen can be

adjusted backwards to

an angle between 12

and 35 degrees.

When changing the

angle, make sure to hold

the stand and adjust to

the best viewable angle.

Round lock for Kensington

Security Standard Slot.

LC-20S1M

LOCATION OF USERS CONTROL (Continued)

Remote control

Displays the TV menu.

SUBTITLE

Displays the Teletext

Subtitle directly.

HOLD

Temporarily holds the

current Teletext page.

MUTE

Switches the sound on and off.

Yellow

Cyan

CHANNEL SELECT

VOL (+)/(

)

(FLASHBACK)

Returns to the previous

channel.

Red

Upwards/ Downwards

Selection, zoom display

function (Teletext mode)

END

TEXT

Displays the Teletext mode

screen.

POWER

MPX

Switches Audio

mode.

REVEAL

Displays hidden inf or mation

such as solutions to r iddles

and puzzles .

Right / Left Selection

SUBPAGE

Displays the Teletext

Subpage directly .

TV/VIDEO

Switches the input source

between AV1, AV2, COMPONENT

and TV mode.

BRIGHT

Selects the brightness

of the display.

Green

CHVOL

SLEEP DIS.MODE

OKMPX

SUBTITLE END

HOLD

SUBPAGE

REVEAL

TEXTBRIGHT

TV/VIDEOPOWER

SLEEP

DIS.MODE

DISPLAY

Press: Displays received channel

for 10 seconds. Channel

indicator reduces in size

after about 10 seconds.

Press again: Display disappears.

CH ( )/( )

Selects next higher channel.

Selects next lower channel.

Batteries for Remote Control

Before using the LCD TV set for the first time, install two (“AAA” size, UM/SUM-4) batteries (supplied).

When the batteries become depleted and the remote control fails to operate, replace the batteries with

new (“AAA” size, UM/SUM-4) batteries.

Open the battery

cover.

Insert two (“AAA” size,

UM/SUM-4) batteries.

Close the battery

cover.

Slide the cover while

pressing the ( ) part.

Position the positive and

negative ends of the

batteries as indicated in the

compartment.

Engage the claw on the

cover into the battery

housing and slide shut.

ËË

404

LC-20S1M

DIMENSIONS

Unit: mm

172

336

156

PRESET

356

474

283

263

244

107

134

403.3

100

411

300.8

228.5

100

160

198

LC-20S1M

REMOVING OF MAJOR PARTS

1. Remove the stand fixing screws (4 pcs.).

2. Remove the terminal cover.

3. Remove the terminal section fixing screws (3 pcs.).

4. Remove the cabinet B fixing screws (9 pcs.).

5. Remove the cabinet B after opening from the direction of an arrow.

6. Remove the reinforcement angle fixing screws (2 pcs.).

7. Detach the connector from each PWB.

Terminal Cover

Reinforcement Angle

Cabinet A

Cabinet B

Stand

Inverter

P6706

P6700

P6701

P6702

P6703

P6704

PWB

Sub PWB

P4001

P3701

P701

P3604

P2001

P3603

SC1202

Main PWB

SC1204

SC1203

P3303

SC3401

P5602

P4003

7 7

R/C, LED

P3302

SC2001

PWB

LC-20S1M

8. Remove the 3 lock screws from the main PWB and undo the hooks a and b. Lifting the other PWBs close to the hooks, draw out the main PWB.

9. Remove the 4 lock screws from the sub PWB and undo the hooks c and d. Detach the chassis frame (right), together with its terminals, from the sub PWB. Undo the hooks e and f in the same way. Detach the chassis frame (left), together with its terminals, from the sub PWB.

10. Remove the 3 lock screws from the inverter PWB and take out the inverter PWB.

11. Remove the 2 lock screws from the R/C, LED PWB and take out the R/C, LED PWB.

12. Remove the 4 lock screws each from the right and left speakers and take out both the speakers.

Chassis Frame (R)

Sub PWB

Main PWB

Chassis Frame (L)

LCD panel unit

Inverter PWB

Speaker (R)

R/C, LED PWB

Speaker (L)

LC-20S1M

» Precautions in handling the LCD panels

1. Work in a clean room (with humidities below 50%).

2. Be sure to wear an anti-static armband.

3. Handle the panels on an electro-conductive mat.

4. Be careful not to fall, shake and shock the panels.

13. Remove the 3 lock screws from the LCD panel and detach the LCD panel.

14. Remove the reflection/polarization sheet, Prism sheet, diffusion sheet and diffusion panel.

15. Detach the lamp holders (top)-A, (top)-B and (bottom) from the lamp unit assembly.

16. Detach the reflection sheets (top) and (bottom) from the back shield.

Back Shield Ass'y

(CSLDMA251WJ01)

Reflection Sheet (Top)

(PSHEPA103WJZZ)

Lamp Holder (Bottom)

(LHLDZA213WJKZ)

Lamp Unit Ass'y

(CLMP-A024WJ01)

Reflection/Deflection Sheet

(PSHEPA101WJZZ)

Diffusion Sheet

(PSHEPA127WJZZ)

20" LCD Panel Unit

Lamp Holder (Top)-A

(LHLDZA211WJKZ)

(PCOVUA014WJZZ)

Prism Sheet

(PSHEPA102WJZZ)

Reflection Sheet (Bottom)

(PSHEPA104WJZZ)

Lamp Clip

(LHLDZA214WJKZ)

Lamp Holder (Top)-B

(LHLDZA212WJKZ)

Diffusion Panel

LC-20S1M

Precautions at the time of the side B(back) service of Main unit.

1. Remove the FFC for connection between Main unit (SC2001) and Sub unit(SC3401), and connect the extended cable (QCNW-A556WJZZ) for service.

2. Remove only SC1204 of the FFC for connection between Main unit (SC1204) and LCD panel unit, and connect the extended cable (QCNW-A553WJZZ) for service.

3. Remove the FFC for connection between Main unit (SC1203) and LCD panel unit, and connect the extended cable (QCNW-A556WJZZ) for service.

4. Remove the FFC for connection between Main unit (SC1202) and LCD panel unit, and connect the extended cable (QCNW-A555WJZZ) for service.

5. Remove the main unit fixing screws (3 pcs.), a substrate is reversed.

Precautions at the time of the side B(back) service of Inverter unit.

6. Remove only P6706 of the cable for connection between Inverter unit (P6706) and Sub unit(P3604), and connect the extended cable (QCNW-B749WJQZ) for service.

7. Remove the Inverter unit fixing screws (3 pcs.), a substrate is reversed.

Sub PWB

P6706

P3701

P3604

Inverter

PWB

(Side B)

Inverter PWB

SC3401

SC1204

P4001

R/C, LED PWB

P701

Main PWB

(Side B)

SC1202SC1203

P2001

SC2001

Step Part No. Description

1 QCNW-A556WJZZ Extension Cable 50-pin Main (SC2001)-Sub (SC3401) 2 QCNW-A553WJZZ Extension Cable 30-pin Main (SC1204)-LCD Panel 3 QCNW-A556WJZZ Extension Cable 50-pin Main (SC1203)-LCD Panel 4 QCNW-A555WJZZ Extension Cable 20-pin Main (SC1202)-LCD Panel 6 QCNW-B749WJQZ Extension Cable 10-pin Inverter (P6706)-Sub(P3604)

LC-20S1M

ADJUSTING PROCEDURE OF EACH SECTION

The best adjustment is made before shipping. If any position deviation is found or after part replace is performed, adjust as follows.

Preparation for Adjustments

Use the exclusive-use AC adapter or stable DC power supply.

AC adapter: UADP-A043WJPZ DC power supply: 12 ± 0.5V 5.0A

1. Adjustment Procedure

1-1. Adjusting the checker

Turning on the power (initialization) → Setting the model and size in inches → Transferring the model-specified data to the E2PROM (I2C) → Calling the adjustment process mode → Starting the adjustment (+B adjustment)

1-2. Adjusting the finish process

Reassembling the set → Turning on the power → Calling the adjustment process mode (using the remote controller) → Adjusting the counter bias, TV contrast and white balance

2. Calling the MAIN adjustment process mode

There are the following two ways to choose from.

• Set the Pin (81) (KEY4) or Pin (82) (KEY5) of IC2001 (microprocessor) to "L", turn on the power.

• For servicing, hold down the "TV/VIDEO" and "MENU" keys at once, and turn on the "POWER" switch. (Make

sure the process mode "K" appears at the top left of the screen.) Then press the "CH (Ù)" and "VOL (–)" keys at once. (Make sure the adjustment process mode screen shows up.) To quit this mode, turn off the power. (Or turn off the "POWER" switch or use the remote controller’s "OFF" key.)

3. Using the keys for the adjustment process

Selecting a reception channel

• Using the "CH (ù)/(Ù)" key, turn up and down reception (broadcasting) channels. Just click on the key, and channels are selected on by one. Hold down the key, and the next receivable channel is searched up and down.

• Adjustment items Adjust each of the items by using the "MENU", "CURSOR UP/DOWN" and "VOL (+)/(–)" keys (on the set or on the remote controller).

• Select an adjustment item using the "CURSOR UP/DOWN" key.

• An adjustment item is toggled on and off by activating the MENU SELECT key (next item).

Let’s suppose that the item at the bottom of a page is now selected. When the "MENU" key is activated here, the item at the top of the next page will be selected.

4. Initialization

4-1. Set pins (81) and (82) of IC2001 (microprocessor) to GND. Turn on the power. 4-2. Select the inch size (20). 4-3. Select the model number "A641M".

~Once "A641M" has been selected, the screen shuts off and the power turns off. But the power turns

itself on to get the set restarted. (The microprocessor resets itself due to a change in model number.)

LC-20S1M

5. Adjustment

5-1. +B adjustment (R3710 Variable resistor)

1) Receive the colour bar signal.

2) Adjust the voltage at pin (4) of P3701 to 5.00 ± 0.02 V. Note: The 5.0 V level is used as reference for all the line voltages. Make this adjustment as precisely as

possible.

5-2. Counter bias adjustment: COM BIAS on page 2

Adjust the "COM BIAS" setting until the contrast gets optimum (the black portion blackest). The adjustment guideline is around 95.

5-3. TAMP adjustment

1) Feed the colour bar pattern signal.

2) See if the "Y" reading on adjustment process page 2 is within the range shown below. If not, adjust the

"NTSC TAMP" setting to bring the "Y" reading within the specified range.

Model LC20S1M

Adjustment value 187~202

3) If the "NTSC TAMP" setting has been readjusted, write down its new setting in the "PAL TAMP" and

"SECAM TAMP" items manually.

(Page 2 of adjustment process OSD)

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

0 1 2 3 4 5 6

COM B I AS TAMP L 817

YD TA TAMP

NTSC TAMP PAL TAMP 26 SECAM

TAMP

Y Data

(White 75%)

918 022

5-4. White balance adjustment

1) Feed the monoscope pattern signal.

2) Adjust the "RCUTOFF", "BCUTOFF", "R-GAIN" and "B-GAIN" settings on adjustment process page 3 to

achieve the colour at the same level as with the standard set.

LC-20S1M

5-5. Other adjustments (SOUND, VPC, DPS, DAC, TUNER, OTHERS, TEXT)

1) Move the cursor to a desired item on page 4 of adjustment process menu. Press the CURSOR LEFT/ RIGHT keys, "VOL (+)/(–)" keys or OK key to select the item.

4 I2C DATA 000000000000 I2C DATA WAIT SOUND VPC DPS DAC TUNER OTHERS TEXT

2) The adjustment process menu of the item appears on the screen. The settings are now ready to change.

Screen with SOUND selected

SOUND1 VOLUME 0 AVC OFF MSP DATA 0000000000 MSP DATA WAIT 0018H ST 1D ONTA 1 CARRIER MUTE ON SP TEST OFF

3) To go back to page 4 of adjustment process menu, press the FLASHBACK key on the remote controller.

6. Lamp error detection

M O D E L A641M I N C H S I Z E 20 E R R O R N O R E S E T 5 P U B L I C M O D E ON E X T C O N T R O L OFF V P C S H A R P N E S S ON V P C F P 2 F H R E A D ON

V E R R O M 1. 0 0A G AI B U 0. 0 0 0

Reset 0

6-1. Functional description

This LCD colour television has a function (lamp error detection) to be turned off automatically for safety when the lamp or lamp circuit is abnormal. If the lamp or lamp circuit is abnormal, or some other errors happen, and the lamp error detection is executed, the followings occur. 1 The main unit of television is turned off 5 seconds after it is turned on. (The power LED on the front side of

TV turns from green to red.)

2 If the situation 1 happens 5 times sequentially, television can not be turned on. (The power LED remains

red.)

6-2. Countermeasures 6-2-1. Check when turning off the lamp error detection

When television is turned off by the lamp error detection mentioned above, it enters the adjustment process with the power LED red. Entering the adjustment process turns off the error detection and turns on TV. This enables the operation check to detect errors in the lamp or lamp circuit. Check whether "ERROR NO RESET" on line 4, page 1 of the adjustment process is 1 or more. If it is 1 or more, it indicates the lamp error detection was executed.

6-2-2. Resetting of the lamp error count

After confirming that the lamp or lamp circuit is normal, reset the lamp error count. Select "ERROR NO RESET" on line 4, page 1 of the adjustment process and set the number to 0 using the volume button.

LC-20S1M

Page 1 of the adjustment process

Afterwards, perform the operation check to confirm that the lamp error detection does not function.

LC-20S1M

7. Public mode

• How to enter into PUBLIC MODE

1. Turn off TV by pressing MAIN POWER switch.

2. While pressing "VOL(+)" key and "CH(ù)" key at the same time, press MAIN POWER switch for more than

2 seconds. TV will turn on, and you will see the screen display a setting of PUBLIC MODE.

• Setting screen of “PUBLIC MODE”

PUBLIC MODE MAXIMUM VOLUME [ 60] VOLUME FIXED [VARIABLE] REMOTE CONTROL [RESPOND] USER CONTROL [RESPOND] MENU BUTTON [RESPOND] ON SCREEN DISPLAY [YES ] START MODE [NORMAL ] INPUT MODE FIXED [VARIABLE] SOUND ONLY MODE [NO ] RESET ENTER

1 ↔ 2 ··· ↔ 59 ↔ 60 VARIABLE ↔ FIXED RESPOND ↔ LIMITED ↔ NO RESPOND RESPOND ↔ NO RESPOND RESPOND ↔ NO RESPOND YES ↔ NO NORMAL ↔ AV1 ↔ COMPONENT ↔ CH1 ↔ CH2 VARIABLE ↔ FIXED NO ↔ YES

↔ CH99 ↔ CH0

...

↔ CH98

Factory setting

Adjust setting

1. You can select each item of functions by pressing cursor UP/DOWN keys or CH(ù)/(Ù) Keys on the remote

control or CH(ù)/(Ù) keys on the LCD TV. The letter of selected item turns to yellow colour when you selected it.

2. The setting position of each item of functions are made by pressing cursor RIGHT/LEFT keys on the remote

control or VOL (+)/(–)keys on the LCD TV.

3. Select ENTER position after you set all functions, and press cursor RIGHT/LEFT keys on the remote control

or VOL(+)/(–)keys on the LCD TV for confirmation. Unless otherwise you make ENTER confirmation, the settings will not be memorized.

• 6-functions of Public Mode settings expand for public application

1. MAXIMUM VOLUME (1—————60)

You can set the maximum volume at your desire level.

2. VOLUME FIXED (VARIABLE / FIXED)

You can fix the sound volume at your desire level. When you set to "FIXED", the sound volume which you just set is fixed.

3. REMOTE CONTROL (RESPOND / LIMITED)

If you set "LIMITED", remote control keys of POWER, CH(ù)/(Ù), VOL(–)/(+) and BRIGHT keys are responded, but other keys are not responded. This is a position that you can not make MENU adjustments.

4. USER CONTROL (RESPOND / NO RESPOND)

"NO RESPOND" means that the TV does not respond when you press a user control buttons except main power button on the main unit.

5. MENU BUTTON (RESPOND / NO RESPOND)

With "NO RESPOND" selected, the remote controller and the set's MENU key are disabled.

6. ON SCREEN DISPLAY (YES / NO)

If you set "NO" position, OSD will not appear.

7. START MODE (NORMAL↔AV1↔COMPONENT↔CH1↔CH2

...

↔CH98↔CH99↔CH0) When any other item than "NORMAL" has been selected, the set gets started in the selected input mode or channel at the next switch-on.

8. INPUT MODE FIXED (VARIABLE↔FIXED) (* This item cannot be selected if the start mode is "NORMAL".) If "FIXED" has been selected, any channels and input modes other than those selected in the start mode cannot be picked up.

LC-20S1M

9. SOUND ONLY MODE (NO↔YES) (* This item cannot be selected if "NO" appears on the on-screen display.) Let's suppose that this item has been selected and the BRIGHT key on the remote control has been pressed. The item "BRIGHTNESS [OFF]" can now be selected next to the item "BRIGHTNESS [DARK]".

Screen with "BRIGHTNESS [OFF]" selected

Count-down started from 5

BRIGHTNESS [OFF] TURNS OFF IN 5 SECS.

Five seconds later, the screen shuts off and the sound alone is heard. Once in this mode, no picture but the OSD appears. But the channels and sound volume can still be changed.

To quit this mode, press the BRIGHT key on the remote control again and select any item other than "BRIGHTNESS [OFF]".

10. RESET You can cancel all Public Mode settings. (It returns to the factory setting.)

11. ENTER You make sure after you have specified all functions, then press the enter key. Unless otherwise you press the enter key, all positions that you have selected will not be set.

LC-20S1M

TROUBLE SHOOTING TABLE

No or Wrong Picture

Does the IC801 test pattern appear properly?

Yes

Check the IC801 signal output line, IC801 itself and its peripheral circuits.

Are the waveforms at the signal input pins of IC801 as specified? TV/Composite Pin (73) S Video Pins (72) and (73) Component Pins (1), (2), (3) and (75)

Yes

Does the IC1201 test pattern appear properly?

Yes

Check IC1201 and its peripheral circuits as well as the LCD panel voltage and waveform.

Are the waveforms at pins (8), (9), (26) and (27) of IC1201 as specified?

Yes

Check the related lines, IC801 itself and its peripheral circuits.

Check IC801 and its peripheral circuits.

Check the IC801 signal input line.

Check all the settings on the microprocessor s adjust process menu.

Are inputs

and outputs

of IC801 as

specified?

Does the DPS

test pattern

appear?

Does the

video decoder

test pattern

appear?

Check IC3401,

IC3402 and its

peripheral

parts.

Check

IC1201, its

peripheral

circuits and

the LCD

panel.

Check IC801

and its

peripheral

circuits.

Are inputs and

outputs of

IC3401, IC3402

as specified?

Check IC3401,

IC3402 and its

peripheral

parts.

Is input at Pin

(73) of IC801

as specified?

Check IC801,

AV1 line and

their

peripheral

parts.

Are inputs and

outputs of

Q1602, Q1604

and Q1606 as

specified?

Check Q1602,

Q1604, Q1606

and its

peripheral

parts.

Is output at

pins (57)~(59)

of IC1601

normal?

Check the R,

G and B line.

Is input at

pin (21) of

IC1601

normal?

Check V2V0

line and its

peripheral

parts.

Check IC1601

and its

peripheral

parts.

Is input at

Pins (1), (2),

(3) and (75)

of IC801 as

specified?

Check J3402,

DVD-Y line,

PB line, PR

line and

peripheral

parts.

Are voltages

at Pins (6),

(7) and (9) of

tuner as

specified?

Check the

power line.

Is output at

Pin (19) of

tuner as

specified?

Check the

tuner and its

peripheral

parts.

Is input at Pin

(5) of IC3402

as specified?

Check the

line in

question.

Check IC3402

and its

peripheral

parts.

Is Pin (4) of

IC3402 at H?

Is Pin (48) of

IC2001 at H?

Check the

line in

question.

Which S

terminal input

does not

work?

Check

SC3412, pin

(1) of IC3401

and the

related line.

Check

SC3411, pin

(16) of IC3401

and the

related line.

Check input

pins (72) and

(73) of IC801,

IC3401 and the

related line.

S terminal for AV1

S terminal for AV1 and AV2

S terminal

for AV2

No picture

at all

No VIDEO

1 or 2

output

No TELE

TEXT

output

No S

VIDEO

output

COMPONENT

output

No TV

output

Yes

TROUBLE SHOOTING TABLE (Continued)

LC-20S1M

Do F3701 and F3301

function?

Check all the settings on the microprocessor s adjust process menu.

Are secondary outputs

(+31V, +9V, +5V, -11V) of

T3701 as specified?

Are the oscillation waveform

at T3701 s primary side as

specified?

Disconnect F3701 and

F3301. Is the load side

short-circuited?

Is any of T3701 s primary

side, Q3703 and S4053 short-

circuited?

Check J3701, its peripheral

parts and connection cable.

Replace F3701 and F3301.

Check S4053 and

connection cable.

Check the secondary-side

load of T3701.

Do F6700, F6701,

F6702, F6703 and

F6704 function?

Is Pin (120) of IC1201 at H ?

Are the oscillation waveforms

at the primary side of T6700,

T6701, T6702, T6703, and

T6704 as specified?

Replace F6700, F6701,

F6702, F6703 and F6704.

Check the line, IC1201 and

its peripheral parts.

Check Q6700 - 6716, T6700

- 6704 and their peripheral

parts.

Replace the fluorescent lamp

and check the oscillation

waveform again.

Is input at Pin (72) of IC801

as specified?

Check SC3411, SC3412, SC

line and peripheral parts.

Check all the settings on the microprocessor s adjust process menu.

Is input at Pins (1), (2) and (3)

of IC801 as specified?

Check J3404, PB line, PR line

and peripheral parts.

No picture and sound

Yes

Fluorescent lamp failure

Yes

No colour

No TV colour No S-VIDEO colourNo VIDEO colour No COMPONENT colour

No No

TROUBLE SHOOTING TABLE (Continued)

Is Pin (53) of

IC2001 at L ?

Check all the settings on the microprocessor s adjust process menu.

Are outputs at

Pins (1) and (7)

of IC3302,

IC3303, IC3304

as specified?

Are inputs at

Pins (2) and (4)

as well as

outputs at Pins

(8) and (12), all

of IC3305, as

specified?

Muting effect is

on. Check the

FSMUTE line.

Check IC3302-

3304 and their

peripheral parts.

Are input and

output of

IC3301 as

specified?

Check IC3304

and its

peripheral parts.

Check the line

in question,

IC3304 and its

peripheral

parts.

Check the

speakers and

their peripheral

parts.

Check the

headphone and

its peripheral

parts.

Is Pin (58) of

IC2001 at L ?

Are outputs at

Pins (14) and

(15) of IC3501

as specified?

Check the line

in question.

Check the

LMUTE line.

Check IC3501,

IC3301 and its

peripheral

parts.

Is output at Pins

(15) and (16) of

tuner as

specified?

Is input at Pin

(67) of IC3301

as specified?

Check IC3304,

X3301 and

their peripheral

parts.

Check the

tuner and its

peripheral

parts.

Check Q3201,

Q3202 and

their peripheral

parts.

No sound

from

speakers

No sound

from

headphone

No sound

from output

line

TV sound

failure

Yes

LC-20S1M

CHASSIS LAYOUT

INVERTER Unit SUB Unit

R/C, LED Unit

87109654321

LC-20S1M

MAIN Unit

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