Sharp Aquos LC-20S1M User manual

LC-20S1M
SERVICE MANUAL
MODEL LC-20S1M
SHARP CORPORATION
LCD COLOURTELEVISION
In the interests of user-safety (Required by safety regulations in some countries) the set should be re-
stored 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 OFTHE SET ..............................................................................................................................75
Page
S73F5LC-20S1M

2
LC-20S1M
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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
components having such features are identified by“ å”
IMPORTANT SERVICE SAFETY PRECAUTION
ËService work should be performed only by qualified service technicians who are
thoroughly familiar with all safety checks and the servicing guidelines which follow:
and shaded areas in the Replacement Parts Lists and
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.
WARNING
1. For continued safety, no modification of any circuit
should be attempted.
2. Disconnect AC power before servicing.
TO EXPOSED
METAL PARTS CONNECT TO
KNOWN EARTH
GROUND
•Use an AC voltmeter having 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.
BEFORE RETURNINGTHE 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 AC 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.
CAUTION: FOR CONTINUED PROTECTION
AGAINST A RISK OF FIRE REPLACE ONLYWITH
SAMETYPE 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.
DVM
AC SCALE
50k ohm
10W
0.15 µF
TEST PROBE

3
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:
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 service 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, remove 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 alloyed 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.
Indicates lead-free solder of tin, silver and copper.
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
LFa

4
LC-20S1M
SPECIFICATIONS
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
2
Lamp life 60,000 hours
Viewing angles H: 170°V: 170°
Audio output 2.1 W 2
Speakers AV1 Composite Video, S-Video, Audio
AV2 IN/OUT Composite Video, S-video, Audio IN/Composite Video, Audio OUT
COMPONENT Y, P
×
××
B, PR/Audio
Headphone jack 3.5 mm øjack (Front)
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,
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.
MODEL LC-20S1M
19.7”(50cm) Advanced Super
View & BLACK TFT LCD
6.3 kg
w/o accessories
ITEMS
4 7 cm, 2 pcs.
Terminals

5
LC-20S1M
OPERATION MANUAL
LOCATION OF USERS CONTROL
Main unit (front view)
12
35
PRESET 1
2
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
MENU
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
P
R
AUDIO (L)
P
B
VIDEO
AUDIO (R)
AUDIO (L)
COMPONENT
AUDIO (L)
AUDIO (R)
VIDEO
Y
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.

6
LC-20S1M
LOCATION OF USERS CONTROL (Continued)
Remote control
MENU
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
OK
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 ormation
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
CH
MENU
E
M
T
CHVOL
MENU
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.
1
Open the battery
cover.
2
Insert two (“AAA”size,
UM/SUM-4) batteries.
3
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.
ËËË

7
LC-20S1M
DIMENSIONS
Unit: mm
PRESET 1
2
474
403.3
107
283
35
244
263
160
411
228.5
300.8
5
100
100
47
68
134
198
172
12
156
336
404
356

8
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.
Cabinet A
Cabinet B
Stand
Terminal Cover
4
3
2
5
1
P6706
SC1204
P3701 P3603
P701
P3303 P3302
P2001
P4001
P4003
SC1202 SC1203
SC2001
P6706
P6701
P6702
P6703
P6704
P6700
P5602
SC3401
P3604
7
7
7
7 7
7
7
7
7
7
6
Inverter PWB R/C, LED PWB
Main PWB
Sub PWB
Reinforcement Angle

9
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.
9
10
12 12
11
8
c
d
ab
f
e
Sub PWB Main PWB
Chassis Frame (R)
Chassis Frame (L)
Inverter PWB
LCD panel unit
R/C, LED PWB
Speaker (R) Speaker (L)

10
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.
13
13
13
14
Diffusion Sheet
(PSHEPA127WJZZ)
Prism Sheet
(PSHEPA102WJZZ)
Diffusion Panel
(PCOVUA014WJZZ)
Lamp Holder (Top)-B
(LHLDZA212WJKZ)
Lamp Clip
(LHLDZA214WJKZ)
Reflection Sheet (Bottom)
(PSHEPA104WJZZ)
Reflection Sheet (Top)
(PSHEPA103WJZZ)
Lamp Holder (Bottom)
(LHLDZA213WJKZ)
Lamp Unit Ass'y
(CLMP-A024WJ01)
Lamp Holder (Top)-A
(LHLDZA211WJKZ)
Back Shield Ass'y
(CSLDMA251WJ01)
Reflection/Deflection Sheet
(PSHEPA101WJZZ)
20" LCD Panel Unit
16
15

11
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.
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)
SC1204
P3701 P3604
P701
P2001
P4001
SC1202SC1203
SC3401
P6706
SC2001
R/C, LED PWB
4
1
5
2
3
Inverter PWB
6
7
Main PWB
(Side B)
Inverter
PWB
(Side B)
Sub PWB

12
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.)

13
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.
3) If the "NTSC TAMP" setting has been readjusted, write down its new setting in the "PAL TAMP" and
"SECAM TAMP" items manually.
Model LC20S1M
Adjustment value 187~202
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
2COM B I AS 95
TAMP L 817
YD TA
H918
TAMP
A022
NTSC TAMP
TAMP
26
PAL TAMP 26
SECAM 26
0
1
2
3
4
5
6
7
Y Data
(White 75%)
(Page 2 of adjustment process OSD)
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.

14
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.

15
LC-20S1M
6. Lamp error detection
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.
1M 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
Page 1 of the adjustment process
Afterwards, perform the operation check to confirm that the lamp error detection does not function.

16
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”
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.
Factory setting
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... ↔CH98
VARIABLE ↔FIXED
NO ↔YES
Adjust setting
↔CH99 ↔CH0

17
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]".
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.
Screen with "BRIGHTNESS [OFF]" selected
BRIGHTNESS [OFF] TURNS OFF IN 5 SECS.
Count-down started from 5

18
LC-20S1M
TROUBLE SHOOTINGTABLE
No orWrong
Picture
Does the IC801
test pattern appear
properly?
Does the IC1201 test
pattern appear
properly?
Check the IC801 signal
output line, IC801 itself
and its peripheral
circuits.
Are the waveforms at
pins (8), (9), (26) and
(27) of IC1201
as specified?
Check IC1201 and its
peripheral circuits as
well as the LCD panel
voltage and waveform.
Check the related lines,
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)
Check the IC801 signal
input line.
Check IC801 and its
peripheral circuits.
No
No
No
No
Yes
Yes
Yes
Yes

19
LC-20S1M
TROUBLE SHOOTINGTABLE (Continued)
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
No picture
at all NoVIDEO
1 or 2
output
NoTELE
TEXT
output
No S
VIDEO
output
No
COMPONENT
output
NoTV
output
Yes
No
Yes
No
No
No
Yes
No
No
Yes
Yes
No
No
Yes
No
Yes
No
Yes
No
No
Yes
Yes
No
Yes

20
LC-20S1M
TROUBLE SHOOTINGTABLE (Continued)
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
No
No
Yes
Yes
No
Yes
No
Fluorescent lamp failure
Yes
No
Yes
No
Yes
No
Yes
Yes
No colour
NoTV colour No S-VIDEO colourNoVIDEO colour No COMPONENT colour
No No