Sharp LC-20B2UB, LC-20B2UA User Manual
LC-20B2UA
LC-20B2UB
SERVICE MANUAL
S42I5LC20B2UB
LCD COLOR TELEVISION
LC-20B2UA
MODELS
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.
LC-20B2UB
OUTLINE
The 20" LCD panel used in the LC-20B2UA has been redesigned as from the April production. Accordingly, the
circuitry and the adjustment procedures have been partially changed.
This Service Manual covers all the changes.
The LC-20B2UB is a sister model with a different cabinet color.
CONTENTS
Page Page
» IMPORTANT SERVICE SAFETY
PRECAUTION.................................................... 2
» SPECIFICATIONS ............................................. 5
» OPERA TION MANUAL ...................................... 6
» DIMENSIONS .................................................... 8
» REMOVING OF MAJOR PARTS ....................... 9
» ADJUSTING PROCEDURE OF
EACH SECTION .............................................. 12
» TROUBLE SHOOTING TABLE ........................ 22
» CHASSIS LA YOUT .......................................... 26
» BLOCK DIAGRAM ........................................... 28
» DESCRIPTION OF SCHEMATIC DIAGRAM .. 30
» SCHEMATIC DIAGRAM
Ë
CONTROL and RC/LED UNIT .................. 31
Ë
DIGITAL UNIT............................................ 32
Ë
ANALOG UNIT .......................................... 42
Ë
INVERTER-A UNIT.................................... 46
Ë
INVERTER-B UNIT.................................... 47
» PRINTED WIRING BOARD ASSEMBLIES..... 48
» P ARTS LIST
Ë
ELECTRICAL PARTS ................................ 62
Ë
DIGITAL UNIT............................................ 62
Ë
ANALOG UNIT .......................................... 67
Ë
CONTROL UNIT........................................ 70
Ë
RC/LED UNIT ............................................ 70
Ë
INVERTER-A UNIT .................................... 70
Ë
INVERTER-B UNIT.................................... 71
Ë
CABINET AND MECHANICAL PARTS ..... 72
Ë
ACCESSORIES P AR TS ............................ 74
Ë
P ACKING PARTS....................................... 74
» PACKING OF THE SET ................................... 75
SHARP CORPORATION
This document has been published to be used for
after sales service only.
The contents are subject to change without notice.
LC-20B2UA
2
2
LC-20B2UB
IMPORTANT SERVICE SAFETY PRECAUTION
Ë
Service work should be perfomed 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 ONL Y WITH SAME
TYPE F3701 (2.0A, 125V), F3702
(1.6A, 125V), F6700 (1.0A, 125V),
A V
F6701 (1.0A, 125V), F6702 (1.0A,
125V), F6703 (1.0A, 125V) AND
F6704 (1.0A, 125V) 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 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.
• Use an AC voltmeter having with 5000 ohm per volt, or
higher, sensitivity or measure the AC voltage drop
across the resisor.
• 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
milliamp. 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
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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
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”
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2
Replacement Parts Lists
.
and
LC-20B2UA
2
2
2
LC-20B2UB
PRECAUTIONS A PRENDRE LORS DE LA REPARATION
Ë
Ne peut effectuer la réparation qu' un technicien spécialisé qui s'est parfaitement
accoutumé à toute vérification de sécurité et aux conseils suivants.
AVERTISSEMENT
conduite électrique ou une prise de terre branchée à
la terre.
1. N'entreprendre aucune modification de tout circuit.
C'est dangereux.
2. Débrancher le récepteur avant toute réparation.
• Utiliser un voltmètre CA d'une sensibilité d'au moins
5000Ω/V pour mesurer la chute de tension en travers
de la résistance.
• Toucher avec la sonde d'essai les pièces métalliques
A V
PRECAUTION: POUR LA
PROTECTION CONTINUE CONTRE
LES RISQUES D'INCENDIE,
REMPLACER LE FUSIBLE PAR UN
FUSIBLE DE MEME TYPE F3701
(2.0A, 125V), F3702 (1.6A, 125V),
F6700(1.0A, 125V), F6701(1.0A, 125V),
F6702(1.0A, 125V), F6703(1.0A, 125V),
F6704(1.0A, 125V).
exposées qui présentent une voie de retour au châssis
(antenne, coffret métallique, tête des vis, arbres de
commande et des boutons, écusson, etc.) et mesurer
la chute de tension CA en-travers de la résistance.
T outes les vérifications doivent être refaites après avoir
inversé la fiche du cordon d'alimentation. (Si nécessaire,
une prise d'adpatation non polarisée peut être utilisée
dans le but de terminer ces vérifications.)
Tous les courants mesurés ne doivent pas dépasser
0,5 mA.
VERIFICA TIONS CONTRE L'INCEN-DIE ET
LE CHOC ELECTRIQUE
Dans le cas contraire, il y a une possibilité de choc
électrique qui doit être supprimée avant de rendre le
récepteur au client.
Avant de rendre le récepteur à l'utilisateur, effectuer
les vérifications suivantes.
1. Inspecter tous les faisceaux de câbles pour s'assurer
que les fils ne soient pas pincés ou qu'un outil ne soit
pas placé entre le châssis et les autres pièces
métalliques du récepteur.
2. Inspecter tous les dispositifs de protection comme les
boutons de commande non-métalliques, les isolants,
le dos du coffret, les couvercles ou blindages de réglage
VTVM
ECHELLE CA
50k ohm
10W
et de compartiment, les réseaux de résistancecapacité, les isolateurs mécaniques, etc.
3. S'assurer qu'il n'y ait pas de danger d'électrocution en
vérifiant la fuite de courant, de la facon suivante:
• Brancher le cordon d'alimentation directem-ent à une
0.15 µF
SONDE D'ESSAI
prise de courant de 110-240V. (Ne pas utiliser de
transformateur d'isolation pour cet essai).
• A l'aide de deux fils à pinces, brancher une résistance
de 50 kΩ 10 watts en parallèle avec un condensateur
de 0,15µF en série avec toutes les pièces métalliques
exposées du coffret et une terre connue comme une
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AUX PIECES
METALLIQUES
EXPOSEES
BRANCHER A UNE
TERRE CONNUE
AVIS POUR LA SECURITE
De nombreuses pièces, électriques et mécaniques, dans
les téléviseurs présentent des caractéristiques spéciales
relatives à la sécurité, qui ne sont souvent pas évidentes
à vue. Le degré de protection ne peut pas être
nécessairement augmentée en utilisant des pièces de
remplacement étalonnées pour haute tension,
puissance, etc.
Les pièces de remplacement qui présentent ces
caractéristiques sont identifiées dans ce manuel; les
pièces électriques qui présentent ces particularités sont
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identifiées par la marque " å " et hachurées dans la
liste des pièces de remplacement et les diagrammes
schématiques.
Pour assurer la protection, ces pièces doivent être
identiques à celles utilisées dans le circuit d'origine.
L'utilisation de pièces qui n'ont pas les mêmes
caractéristiques que les pièces recommandées par
l'usine, indiquées dans ce manuel, peut provoquer des
électrocutions, incendies, radiations X ou autres
accidents.
3
LC-20B2UA
LC-20B2UB
Precautions for using lead-free solder
1 Employing lead-free solder
"Digital PWB" 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 40ºC, we recommend
you to use a dedicated soldering bit, if you are not familiar with how to obtain lead-free wire solder or soldening
bit, contact our service station or service ranch 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 wettabillty, 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 excoeded, remove the bit from the PWB as soon as you conurm the steady soldering
condition.
Lead-free solder contains more tin, and the end of the soldering bit may be easily corroded. Make sure to tum 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.
Becareful 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
4
Specifications
LC-20B2UA
LC-20B2UB
Items
LCD panel 19.7” TFT LCD
Number of dots 921,600 dots VGA
Video color systems N358, N443, PAL, PAL-M, PAL-N, SECAM, PAL-60
Destination USA/Latin A/Twn
TV Standard (CCIR) NTSC/PAL-M/PAL-N
TV function TV Tuning System PLL 181 ch.
STEREO MTS+SAP
CATV 125 ch.
3 Dimensional Y/C separation circuit Yes (N358 only)
Digital comb filter Yes
Brightness
Lamp life 60,000 hours
Viewing angles H: 170° V : 170°
Audio amplifier
Speakers
AV1 AV-IN1, S-VIDEO-IN
AV2 AV-IN2/AV-OUT
Terminals COMPONENT COMPONENT-IN, AUDIO-IN
Antenna F-Type
Headphone Mini-jack for stereo (3.5 ø)
OSD language English/French/Spanish
Power Consumption AC 65 W (with AC Adapter), DC 56 W (DC13V)
Power supply DC 13 V, AC 110–240 V, 50/60 Hz
Weight 18.5 lbs (8.4 kg), w/o accessories
Accessories Remote control, Batteries, Antenna cable, AC adapter,
Environmental Conditions 0°C ~ 40°C
Ë
The LCD panel is backed by ultra-high-precision technology and provides for over 99.99% effective pixels.
There may be a pixel dropout of below 0.01% or always-on pixels, but this is not a system failure.
Model
430 cd/m
2.5 W × 2
ø2 in. (5 cm), 2 pcs.
AC cord, Cable clamps
2
LC-20B2UA/B
Design and specifications are subject to change without notice.
5
LC-20B2UA
TV/VIDEO, CH (
)/(
), VOL (+)/(–), and MENU on the main unit have the same functions as the same buttons
on the remote control. Fundamentally, this operation manual provides a description based on operation with the
remote control.
FRONT AND REAR CONTROL OPTIONS
Main unit (front view)
VOL CH MENU TV/VIDEO MAIN POWER
VOL (–)/(+)
CH (
)/( )
MENU
TV/VIDEO
MAIN POWER
Speaker
SLEEP indicator
The SLEEP indicator lights up red when
the SLEEP TIMER is set to on.
Speaker
Upper control panel
Remote sensor window
(The actual location is not visible.)
To change the vertical
angle of the LCD TV set,
tilt the screen up to 5
degrees forward or 10
degrees backward. The
TV set can also be
rotated 50 degrees
horizontally. Please adjust
the angle so that the TV
set can be watched most
comfortably.
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).
V
ID
E
O
A
U
D
IO
L
Y
P
B
P
R
R
A
U
D
IO
L
R
C
O
M
P
O
N
E
N
T
A
V
-IN
2
/O
U
T
Main unit (rear view)
AUDIO (L)
AUDIO (R)
AUDIO (L)
AUDIO (R)
VIDEO
Y
P
R
P
B
AV-IN2/OUT
COMPONENT
AUDIO (L)
AUDIO (R)
VIDEO
S-VIDEO
AV-IN1
HEADPHONE
POWER INPUT
(DC 13V)
V
ID
E
O
S
-V
ID
E
O
A
N
T
.
P
O
W
E
R
IN
P
U
T
D
C
1
3
V
H
E
A
D
P
H
O
N
E
A
U
D
IO
L
R
A
V
-IN
1
Antenna terminal
LC-20B2UB
Operation Manual
6
FRONT AND REAR CONTROL OPTIONS (Continued)
Before connecting a connection cord into the rear terminal,
remove the back cover. Push in the tab and pull out the back
cover carefully.
To mount the cover, insert the 2 hooks on the bottom of the
cover into the cabinet and press on the upper part of the back
cover until the tab locks in place with a click.
Removing the Back Cover
1
4
7
MTS
2
5
8
0
3
6
9
100
POWER
DISPLAY
SLEEP
BRIGHT
MENU
MUTE
TV/VIDEO
CH
VOL
FLASHBACK
REMOTE CONTROL
MENU/
'/"/\/|
(Cursor control)
TV/VIDEO
POWER
DISPLAY*
1
SLEEP
MUTE
VOL(+)/(–)
MTS*
3
BRIGHT
FLASHBACK*
2
CH (
)/( )
Channel Select
*
1
Displays the receiving chan-
nel for 10 seconds.
*
2
Returns to the previous
channel.
*
3
Selects audio settings.
LC-20B2UA
LC-20B2UB
7
LC-20B2UA
LC-20B2UB
Dimensions
/473.5
64
/
41
18-
/381.5
/64
1
15-
24-51/64 /630
15-55/64 /403
/301
/32
27
11-
7
/32 /107.3
4-
2-55/64 /72.6
/468.8
64
/
29
18-
VIDEO
AV-IN2/OUT
AUDIO
COMPONENT
AUDIO
29
14-
/32 /379
VIDEO
AV-IN1
L
AUDIO
R
L
R
Y
P
B
P
R
L
R
S-VIDEO
HEAD
PHONE
ANT.
POWER
INPUT
DC13V
25
2-
/64 /60.8
1
/32 /229.4
9-
(Unit: inch/mm)
8
REMOVING OF MAJOR PARTS
1. Remove the two back covers.
2. Remove the table stand fixing screws (4 pcs.).
3. Remove the rear cabinet fixing screws (14 pcs.) and detach the cabinet.
(3 : XBBSF30P06000, 3 : XEBSF40P16000)
4. Remove the reinforcement angle fixing screws (4 pcs.).
5. Detach the connector from each PWB.
LC-20B2UA
LC-20B2UB
3
Rear Cabinet
3
Back cover
2
3
3
3
1
3
3
3
Table stand
1
Back cover
Reinforcement angle
5
5
RC/LED PWB
5
5
DIGITAL
PWB
5
5
5
5
ANALOG PWB
5
5
CONTROL PWB
5
5
INVERTER-A
5
5
PWB
5
4
5
5
5
5
5
5
INVERTER-B PWB
9
LC-20B2UA
LC-20B2UB
6. Remove the digital PWB fixing screws (3 pcs.).
7. Remove the inverter-A PWB fixing screws (2 pcs.).
8. Remove the inverter-B PWB fixing screws (1 pc.).
9. Detach the chassis frame cover.
10. Remove the analog PWB fixing screws (3 pcs.).
11. Remove the RC/LED PWB fixing screws (2 pcs.).
12. Remove the control PWB fixing screws (2pcs.).
6
Chassis frame
DIGITAL PWB
10
INBERTER-A
PWB
ANALOG
PWB
7
8
INBERTER-B
PWB
9
CONTROL PWB
RC/LED PWB
11
Chassis frame cover
12
10
» 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 electroconductive mat.
4. Be careful not to fall, shake and shock the panels.
14.Remove the four screws and open the LCD display unit.
15.Remove the ITO earth angle fixing screw (1 pc.).
16.Detach the reflection/deflection, prism, diffusion, ITO sheets and diffusion plate.
17.Remove the lamp holder fixing screws (6 pcs.).
18.Detach the lamp set A/B.
19.Remove the reflection plate fixing screws (6 pcs.).
Shielding plate
(CSLDM4685CE02)
Lamp holder
(LHLDZ2176CEZZ)
Diffusion plate
(PCOVU0107CEZZ)
ITO sheet
(PSHEP0289CEZZ)
LC-20B2UA
LC-20B2UB
o
Prism sheet
(PSHEP0287CEZZ)
20" LCD panel unit
r
u
y
t
Diffusion sheet
(PSHEP0288CEZZ)
Reflection/deflection sheet
(PSHEP0286CEZZ)
i
u
Lamp holder
(LHLDZ2176CEZZ)
ITO earth angle
(MSPRP1220CEFW)
Reflection plate
(PMiR-0296CEZZ)
Lamp set-A
(KLMP-0124CEZZ)
Lamp set-B
(KLMP-0125CEZZ)
11
LC-20B2UA
LC-20B2UB
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.
1.Preparation for Adjustments
(1)Use the exclusive-use AC adapter or stable DC power supply.
AC adapter: UADP-0243CEPZ
DC power supply: 13 ± 0.5V
2.Special mode setting procedure
(1)After initialization of E2PROM the mode is changed to the adjustment mode.
[Procedure]
Connect TP2001 and TP2002 to GND, and turn on the power.
[Description]
» The initialization of microprocessor is as follows.
» AV position, DAC data, G/A data, sound processor data, and video chroma data adjustment values are taken as
defaults.
(2)Adjustment mode
[Procedure]
Short-circuit TP2001 to GND, and turn on the power.
Or short-circuit TP2002 to GND, and turn on the power.
Or holding down the [TV/VIDEO] key and [MENU] key, turn on the main power, and simultaneously press the
(inspection process) [CH "] key and [VOL– ] key to change the mode to the adjustment mode.
[Description]
The manual adjustment or adjustment through communication with the automatic machine is performed.
(3)Shipping setting mode
[Procedure]
Holding down the [TV/VIDEO] key and [MENU] key, turn on the main power, and simultaneously press the
(inspection process) [CH '] key and [VOL+] key to change the mode to the shipping setting mode.
Note: Keep it in mind to turn off the power immediately. If any key-in is accidentally made, the setting will be
canceled.
[Description]
User adjustment and other values are taken as defaults.
If TV is indicated as SETTING COMPLETE, setting has been completed.
3.Cancel of special mode
Turn off the main unit power.
12
4.Adjustments
Page 2 of adjustment process mode
2
| COM BIAS 90
NTSCTAMP 20
PAL-M TAMP 20
PAL-N TAMP 20
RCUTOFF -1
GCUTOFF 0
BCUTOFF -1
G3 B3 R3 00 00 00
G1 B4 Y EF C7 C2
TAMP H CA
TAMP L BB
GAIBU VER0.000
“Y” data
(white 75%)
Adjustment Adjusting conditions Adjusting method
LC-20B2UA
LC-20B2UB
1 B+ Adjustment
(R3760)
2 Inch Size setup
(If E2PROM is replaced)
(IC2004)
3 Common-bias adjustment
4 TAMP adjustment
1. Connect the DC voltmeter to
pin 2 of P3702.
1. Go to the adjustment mode.
1. Receive a B/W channel.
2. Go to the adjustment mode.
3. Select the "COM BIAS" with
[MENU] key.
1. Receive a half color bar signal in the
TV mode so that the top left zone
should turn white 75% as shown below. Other signal can be fed instead
of the half color bar signal, however,
if the point at the vertical 180th line
and horizontal 46th pixel is of white
75%. (Make the adjustment based on
the setting of this point.)
1. Adjust the "B+ Adj" value to
5.0±0.02V with R3760. Make exact
adjustment of the 5.00V level because it will be the reference for all
the other supply voltages. Be sure to
make this adjustment together with
the main PWB (digital PWB). During
the adjustment, be also careful not
to allow the voltage at pin (2) of
P3702 to go above 5.3 V.
1. Select "INCH SIZE" and adjust to
"20" with [VOL+] or [VOL-] key.
* The color of "INCH SIZE" must be
yellow.
1. Adjust "COM BIAS" to the darkest
screen with [VOL+] and [VOL-] key.
* The color of "COM BIAS" must be
yellow.
White 75% at
top left zone
Vertical 180th line and
horizontal 46th pixel
640 pixels
480 lines
5 White balance adjustment
6 Checking and modifying
the settings adjustment
(If E2PROM is replaced)
2. Adjust the “NTSC TAMP” setting on
page 2 of adjustment process mode
so that the “Y” reading on the same
page should be BB - CA.
3. Make the same setting for the PALM TAMP and PAL-N TAMP data.
1. Receive the monoscope pattern signal.
2. Adjust the “RCUTOFF” and
“BCUTOFF” settings on page 2 of
adjustment process mode to achieve
an optimum white balance.
Go to the adjustment mode and
check the following settings.
V176 130
V21 45
13
1. Do not change the “GCUTOFF” setting
because otherwise the black level may
fluctuate.
See if all the settings are as specified. If not, select an item in question
with [VOL+] or [VOL-] key and adjust
the setting as shown at left.
* An item selected will be highlighted
in yellow.
LC-20B2UA
LC-20B2UB
Adjustment Adjusting conditions Adjusting method
7E2PROM data write
1. Call up the adjustment process menu
and get Page 6 displayed onscreen.
2. Enter “A40000002681” for the “I2C
DA TA” item in Line 1.
If the wrong data has been sent:
2
1. Initialize the E
PROM. (Take the
special mode setting procedure (1).)
2. Take the adjustment steps 2 thru 7.
3. Move the cursor to the “I2C DATA”
item in Line 2 and carry out “SEND”
with the right cursor key.
5.Shipping setting list
Channel............................................................................................................................................... 2ch
Air/Cable ............................................................................................................................................. Air
Skip Data_CATV................................................................................................................................. All Skip
Skip Data_AIR .................................................................................................................................... All Skip
Volume................................................................................................................................................ 20
Picture................................................................................................................................................. 30
Tint ...................................................................................................................................................... 0
Color ................................................................................................................................................... 0
Black Level ......................................................................................................................................... 0
SHARPNESS...................................................................................................................................... 0
RED-BLUE.......................................................................................................................................... 0
GREEN ............................................................................................................................................... 0
TV Color System................................................................................................................................. N358
AV Color System ................................................................................................................................ N358
Language ............................................................................................................................................ English
Blue Screen ........................................................................................................................................ Off
EZ Setup Auto Start............................................................................................................................ On
Sleep Timer ........................................................................................................................................ None
MTS .................................................................................................................................................... Stereo
Brightness........................................................................................................................................... Bright
Auto Power Off ................................................................................................................................... Off
Upside................................................................................................................................................. Normal
Right/Left ............................................................................................................................................ Normal
AV2 IN/OUT........................................................................................................................................ In
Closed Caption (Mode) ...................................................................................................................... OFF
(Data) ....................................................................................................................... CH1
V Chip block (MPAA)..................................................................................................................... None
(TV Guideline) .......................................................................................................... None
(Block Content) ........................................................................................................ All Unblock
(Status)..................................................................................................................... Off
(Input Secret No.)..................................................................................................... Clear
14
Test patterns in adjustment process mode
[1] IC801 (Video decoder) test patterns
1-1. Getting the test patterns displayed
Put the screen in AV1, AV2 or COMPONENT but keep out any signal. Call the adjustment process mode,
select “TEST PATTERN” in the 3rd line of page 7, make the settings 1 thru 6, and the following test patterns
show up.
1-2. Test patterns
» Setting 1
The color bars are displayed as shown at left.
LC-20B2UA
LC-20B2UB
Yellow
Green
Cyan
Magenta
Green
Red
Blue
greengreen
Yellow
» Setting 2
Finer vertical stripes than Setting 1 are displayed.
» Setting 3
Green
Bright BrightDark
» Setting 4
A rather dark green-only pattern is displayed.
» Setting 5
A half-tone green-only pattern is displayed.
» Setting 6
A rather bright green-only pattern is displayed.
[2] IC1201 (LCD controller) test pattern
2-1. Getting the test pattern displayed
Put the screen in AV1, AV2 or COMPONENT but keep out any signal. Call the adjustment process mode,
select “G/A TEST PATTERN” in the 13th line of page 16, turn on the setting, and the following test pattern
shows up.
2-2. Test pattern
The following test pattern appears.
Cyan
Magenta
The green pattern is displayed as shown at left.
W
h
i
t
gradation
e
Dark
Dark
Dark
Black
0-level
Gray scale
Gray
16-level
gradation
Red
Green
Blue
Gray
32-level
gradation
Bright
Bright
Bright
Bright
Gray
48-level
gradation
DarkDark
Dark
Dark
Dark
White
63-level
gradation
Note: When the IC801 and IC1201 test pattern display commands are both turned on at the same time, the IC1201
test pattern is given priority.
15
LC-20B2UA
LC-20B2UB
Pin functions of microprocessor IC (IC2001) RH-iXA154WJZZQ
No
. Pin name Function
1 V HOLD
2 HLF
3 MAIN SW
4 TIMELED
5 M/S OUT
6 CSYNC
7 IREMI
8 GND
9 GND
10 XCIN
11 XOUT
12 RESET
13 XOUT
14 GND
15 XIN
16 VCC
17 OSCIN
18 OSCOUT
19 PSWIN
20 SUBREADY
21 BLK
22
23 DAC1CS
24 DAC2CS
25 D SW
26 DTV
27 MRDY
28 SCL2
29 SCL1
30 SDA1
31 SDA2
32 R
33 G
34 B
35 SUBD OUT
36 SUBDIN
37 SUBCLK
38
39 MRDY OUT
40 FCH
41 IREM OUT
42 L_ERR
43 S IN/OUT
44 N443
45 PAL
46 SECAM
47 PAL_M
48 N358
49 PXOE
50 VSH OUT
Closed caption
Closed caption
Main switch ON[H]/OFF[L]
Off timer LED light-up
Sub-microprocessor master/slave output
Composite sync signal
Remote control
Grounding
Grounding
32kHz oscillation input
32kHz oscillation output
Reset at “L” level
Microprocessor oscillator connection
Grounding
Microprocessor oscillator connection
Power
OSD clock input
OSD clock output
Main power input
Sub-microprocessor ready input
OSD blanking output
DAC1 chip select
DAC2 chip select
D terminal connection detect
D terminal control line
I2C bus open/closed select input
I2C bus serial clock line 2
I2C bus serial clock line 1
I2C bus serial data line 1
I2C bus serial data line 2
R signal output
G signal output
B signal output
Sub-microprocessor data output
Sub-microprocessor data input
Sub-microprocessor clock input
I2C bus open/closed output
No-signal field ID signal output
Not used
Fluorescent lamp error detect input
Audio input/output select
“H” for N443, “L” for others
“H” for P AL, “L” for others
“H” for SECAM, “L” for others
“H” for P AL-M, “L” for others
“H” for N358, “L” for others
Card (Card mode at “L” level)
Panel gate driver voltage control
No
. Pin name Function
51 REQ
52 AV/SY/DY2
53 FSMUTE
54 RSMUTE
55 HPDET
56 SSTBY
57 VSH IN
58 LMUTE
59 V IN/OUT
60 SRESET
61 DENKA
62 VCC
63 CARDPOW
64 VSS
65 TV/AV1
66 AV/AV2
67 VIS/3DS
68 AV1/VISY
69 AV/SY/DY1
70 STD
71 PMUTE
72 POWOUT
73 AD POW
74 IREM 2
75 MPRCS
76 MPRDA
77 MPCS
78 MPDA
79 MPCLK
80 DDCRESET
81 KEY4
82 KEY5
83 CARDRESET
84 SAW SW
85 MODE1
86 MODE2
87 SSYSTEM
88 SSW
89 AFT
90 AGC
91 KEY1
92 KEY2
93 KEY3
94 POWIN
95 VSYNC
96 AVSS
97 HSYNC
98 TVSETB
99 AVCC
100
CVIN
Adjustment process
US CCD input select
Front mute
Rear mute
Headphone detect at “L” level
Speaker standby (at “H” level)
Panel gate driver voltage check
Line out audio mute
Video input/output select
Multiplex reset at “L” level
Electric charge prevention
Power
Card (ON/OFF)
Grounding
Analog switch 1
Analog switch 2
Analog switch 3
Analog switch 4
US CCD input select 2
Microprocessor power off output
P mute
DC/DC control output
Adaptor ON/OFF input
Reception at slave
G/A read enable
G/A data input
G/A chip select
G/A data output
G/A clock
Digital decoder reset
Key input 4
Key input 5
Card reset (at “H” level)
Tuner select (at “H” level)
Tuner select (at “H” level)
Tuner select (at “H” level)
S system switching detect
S terminal connect input at “L” level
AFT voltage input
AGC voltage input
Key input 1
Key input 2
Key input 3
DC/DC start-up detect
OSD vertical sync signal
Analog power input (GND)
OSD horizontal sync signal
Closed caption (GND)
OSD power input
Closed caption signal input
16
Adjustment process mode menus at a glance
Page Item
Initial setting
Function Adjust/modify
Basic settings
1 INCH SIZE 20 Inch unit select Adjustment
MODEL B2UA Model number
SYSTEM N358 Color system select
NTSC PWN FREQ OCO Dimmer frequency setting
PAL PWM FREQ OBD Dimmer frequency setting
NTSC PWM DUTY 0 Dimmer duty setting
PAL PWM DUTY 0 Dimmer duty setting
TV GAIN OFF Auto gain setting in TV mode
ERROR NO RESET 0 Lamp error count & reset No. of lamp error detections
V-CHIP 1 VCHIP line mute setting
CANADIAN VCHIP OFF Canadian VCHIP setting
B2UAVER Microprocessor Ver. No. display
Video adjustments
2 COM BIAS 90 Counter bias adjustment Adjustment
NTSC TAMP 20 TAMP adjustment Adjustment
PAL-M TAMP 20 TAMP adjustment
PAL-N TAMP 20 TAMP adjustment
RCUTOFF -1 Red cutoff adjustment Adjustment
GCUTOFF 0 Green cutoff adjustment
BCUTOFF -1 Blue cutoff adjustment Adjustment
G3 00 Data read value
B3 00 Data read value
R3 00 Data read value
G1 00 Data read value
B4 00 Data read value
Y DA Data read value at TAMP adjustment
TAMP H CA Y upper limit setting at TAMP adjustment
TAMP L BB Y lower limit setting at TAMP adjustment
3 TV NTSC CONT 51 Video contrast setting (TV NTSC)
TV PAL-M CONT 51 Video contrast setting (TV PAL-M)
TV PAL-N CONT 51 Video contrast setting (TV PAL-N)
AV N358 CONTRAST 49 Video contrast setting (Composite, S Video)
AV PAL CONTRAST 49 Video contrast setting (Composite, S Video)
AV SECAM CONTRAST 49 Video contrast setting (Composite, S Video)
AV PAL-M CONTRAST 49 Video contrast setting (Composite, S Video)
AV PAL-N CONTRAST 49 Video contrast setting (Composite, S Video)
AV PAL60 CONTRAST 49 Video contrast setting (Composite, S Video)
G3 00 Data read value
B3 00 Data read value
R3 00 Data read value
G1 00 Data read value
B4 00 Data read value
Y 00 Data read value
Adjustment (Same setting as for NTSC TAMP)
Adjustment (Same setting as for NTSC TAMP)
LC-20B2UA
LC-20B2UB
Audio adjustments (MSP settings)
4 TV GEQ BAND1 +0.5 Equalizer setting 1 (TV)
TV GEQ BAND2 +0.5 Equalizer setting 2 (TV)
TV GEQ BAND3 +1.0 Equalizer setting 3 (TV)
TV GEQ BAND4 +0.5 Equalizer setting 4 (TV)
TV GEQ BAND5 –1.0 Equalizer setting 5 (TV)
EXT GEQ BAND1 +0.5 Equalizer setting 1 (external input)
EXT GEQ BAND2 +0.5 Equalizer setting 2 (external input)
EXT GEQ BAND3 +1.0 Equalizer setting 3 (external input)
EXT GEQ BAND4 +0.5 Equalizer setting 4 (external input)
EXT GEQ BAND5 –1.0 Equalizer setting 5 (external input)
AVC OFF AVC setting
CARRIER MUTE ON Audio output setting out of sync with TV
IGR THR 12D IGR THRESH LEVEL
5 MSP DATA 0 Audio IC MSP data write & read
MSP DATA WAIT Write & read execution
PRESCALE FM/AM-M 17 Pre-scale setting (TV)
PRESCALE SCART 15 Pre-scale setting (external input)
FSP TEST OFF Audio test (FS mute ON/OFF)
17
LC-20B2UA
LC-20B2UB
Page Item
Initial setting
Function Adjust/modify
Video adjustments (VPC settings)
6 I2C DATA 0 I2C bus control IC data write & read
I2C DATA WAIT Write & read execution
CBW 1 Chroma band pass setting
NOSEL 3 Comb filter setting
DDR 1 Comb filter setting
HDG 3 Comb filter setting
VDG 0 Comb filter setting
VPK 0 Comb filter setting
KILVL 08 08 Color killer level setting
KILHY 05 05 Color killer hysteresis setting
VSYNC DELAY 29 V sync phase setting
DVCO -720 DVCO setting
AUTO LCK 1 Line lock mode setting
Video adjustments (component)
7 VPC DATA 0 Video IC VPC data write & read
VPC DATA WAIT Write & read execution
TEST PATTERN 0 PVC test pattern select Video IC test pattern
AUTO LDLY 0 Y/C phase setting
DVD NTSC CR 25 Color density setting (component)
DVD NTSC CB 25 Color density setting (component)
DVD NTSC TINT +7 Color tone setting (component)
DVD NTSC BRIGHTNESS +68 Brightness setting (component)
DVD NTSC CONTRAST 26 Video setting (component)
DVD NTSC P FILTER 1 Peaking filter setting (component)
DVD NTSC H-PEAKING 3 Picture quality setting (component)
DVD NTSC BRIGHT2 +8 Brightness setting 2 (component)
DVD NTSC CONTRAST2 48 Video setting 2 (component)
8 DVD PAL CR 24 Color density setting (component)
DVD PAL CB 24 Color density setting (component)
DVD PAL TINT + 9 Color tone setting (component)
DVD PAL BRIGHTNESS +68 Brightness setting (component)
DVD PAL CONTRAST 26 Video setting (component)
DVD PAL P FILTER 1 Peaking filter setting (component)
DVD PAL H-PEAKING 4 Picture quality setting (component)
DVD PAL BRIGHT2 +8 Brightness setting 2 (component)
DVD PAL CONTRAST2 48 Video setting 2 (component)
Video adjustments (TV, composite & S video)
9 N358 TV COLOR 2500 Color density setting (TV)
N358 AV COLOR 2500 Color density setting (composite, S video)
N358 TV TINT +40 Color tone setting (TV)
N358 AV TINT +56 Color tone setting (composite, S video)
N358 BRIGHTNESS +8 Brightness setting (TV, composite, S video)
N358 PEAKING FILTER 1 Peaking filter setting (TV, composite, S video)
N358 TV H-PEAKING 4 Picture quality setting (TV)
N358 AV H-PEAKING 4 Picture quality setting (composite, S video)
N358 AVO START 152 Horizontal position setting
N358 SFIF 0 Horizontal position setting
N358 SCINC1 1623 Roundness setting
N358 TV LDLY 0 Y/C phase setting (TV)
N358 AV LDLY 0 Y/C phase setting (composite, S video)
10 N443 AV COLOR 2500 Color density setting (composite, S video)
N443 AV TINT +56 Color tone setting (composite, S video)
N443 BRIGHTNESS +8 Brightness setting (TV, composite, S video)
N443 PEAKING FILTER 1 Peaking filter setting (TV, composite, S video)
N443 AV H-PEAKING 4 Picture quality setting (composite, S video)
N443 AVO START 152 Horizontal position setting
N443 SFIF 0 Horizontal position setting
N443 SCINC1 1623 Roundness setting
N443 AV LDLY 0 Y/C phase setting (composite, S video)
18
LC-20B2UA
LC-20B2UB
Page Item
Initial setting
Function Adjust/modify
Video adjustments (TV, composite & S video)
11 PAL AV COLOR 2500 Color density setting (composite, S video)
PAL AV TINT +56 Color tone setting (composite, S video)
PAL BRIGHTNESS +8 Brightness setting (TV, composite, S video)
PAL PEAKING FILTER 1 Peaking filter setting (TV, composite, S video)
PAL AV H-PEAKING 4 Picture quality setting (composite, S video)
PAL AVO START 152 Horizontal position setting
PAL SFIF 0 Horizontal position setting
PAL SCINC1 1623 Roundness setting
PAL AV LDLY 0 Y/C phase setting (composite, S video)
12 SECAM AV COLOR 2500 Color density setting (composite, S video)
SECAM AV TINT +56 Color tone setting (composite, S video)
SECAM BRIGHTNESS +8 Brightness setting (TV, composite, S video)
SECAM
SECAM AV H-PEAKING 4 Picture quality setting (composite, S video)
SECAM AVO START 152 Horizontal position setting
SECAM SFIF 0 Horizontal position setting
SECAM SCINC1 1623 Roundness setting
SECAM AV LDLY 0 Y/C phase setting (composite, S video)
13 PAL-M TV COLOR 2500 Color density setting (TV)
PAL-M AV COLOR 2500 Color density setting (composite, S video)
PAL-M TV TINT +40 Color tone setting (TV)
PAL-M AV TINT +56 Color tone setting (composite, S video)
PAL-M BRIGHTNESS +8 Brightness setting (TV, composite, S video)
PAL-M PEAKING FILTER 1 Peaking filter setting (TV, composite, S video)
PAL-M TV H-PEAKING 4 Picture quality setting (TV)
PAL-M AV H-PEAKING 4 Picture quality setting (composite, S video)
PAL-M AVO START 152 Horizontal position setting
PAL-M SFIF 0 Horizontal position setting
PAL-M SCINC1 1623 Roundness setting
PAL-M TV LDLY 0 Y/C phase setting (TV)
PAL-M AV LDLY 0 Y/C phase setting (composite, S video)
14 PAL-N TV COLOR 2500 Color density setting (TV)
PAL-N AV COLOR 2500 Color density setting (composite, S video)
PAL-N TV TINT +40 Color tone setting (TV)
PAL-N AV TINT +56 Color tone setting (composite, S video)
PAL-N BRIGHTNESS +8 Brightness setting (TV, composite, S video)
PAL-N PEAKING FILTER 1 Peaking filter setting (TV, composite, S video)
PAL-N TV H-PEAKING 4 Picture quality setting (TV)
PAL-N AV H-PEAKING 4 Picture quality setting (composite, S video)
PAL-N AVO START 152 Horizontal position setting
PAL-N SFIF 0 Horizontal position setting
PAL-N SCINC1 1623 Roundness setting
PAL-N TV LDLY 0 Y/C phase setting (TV)
PAL-N AV LDLY 0 Y/C phase setting (composite, S video)
15 PAL60 AV COLOR 2500 Color density setting (composite, S video)
PAL60 AV TINT +56 Color tone setting (composite, S video)
PAL60 BRIGHTNESS +8 Brightness setting (TV, composite, S video)
PAL60 PEAKING FILTER 1 Peaking filter setting (TV, composite, S video)
PAL60 AV H-PEAKING 4 Picture quality setting (composite, S video)
PAL60 AVO START 152 Horizontal position setting
PAL60 SFIF 0 Horizontal position setting
PAL60 SCINC1 1623 Roundness setting
PAL60 AV LDLY 0 Y/C phase setting (composite, S video)
PEAKING FILTER
1 Peaking filter setting (TV, composite, S video)
19
LC-20B2UA
LC-20B2UB
Page Item
Initial setting
Function Adjust/modify
Search AFT reference settings & LCD controller settings (NTSC)
16 AFT UP 2.7 AFT reference voltage
AFT DOWN 1.8 AFT reference voltage
NTSC 01 8C Initial settings
NTSC 02 C0 Various settings
NTSC 03 81 RCUTOFF
NTSC 04 00 GCUTOFF
NTSC 05 81 BCUTOFF
NTSC 06 0C Horizontal display position
NTSC 07 10 Vertical display position
NTSC 08 00 UV data phase delay
NTSC 09 4C Panel clock adjustment
NTSC 0A 4B Display screen top/bottom mask position
NTSC 10 80 Test pattern display
NTSC 11 00 Test pattern data
NTSC 12 00 Horizontal display mask (left) position
NTSC 13 00 Horizontal display mask (right) position
NTSC E0 00 FIFO TEST
NTSC E1 03 Sync polarity reversal
NTSC F0 07 OFL terminal operation setting
NTSC F1 00 Inverter frequency setting
NTSC F2 00 Inverter duty setting
NTSC F3 C0 Dimmer frequency setting, lower level
NTSC F4 00 Dimmer frequency setting, upper level
NTSC F5 00 Dimmer PWM setting, lower level
NTSC F6 00 Dimmer PWM setting, upper level
NTSC F7 00 OFL 1/2 phase
NTSC 14 02 System clock setting
G/A TEST PATERN OFF Gradation test pattern display LCD controller IC test pattern
LCD controller settings (PAL) & closed caption settings
17 PAL 01 8E Initial settings
PAL 02 C8 Various settings
PAL 03 81 RCUTOFF
PAL 04 00 GCUTOFF
PAL 05 81 BCUTOFF
PAL 06 14 Horizontal display position
PAL 07 18 Vertical display position
PAL 08 O2 UV data phase delay
PAL 09 4C Panel clock adjustment
PAL 0A 4A Display screen top/bottom mask position
PAL 10 80 Test pattern display
PAL 11 00 Test pattern data
PAL 12 00 Horizontal display mask (left) position
PAL 13 00 Horizontal display mask (right) position
PAL E0 00 FIFO TEST
PAL E1 03 Sync polarity reversal
PAL F0 07 OFL terminal operation setting
PAL F1 00 Inverter frequency setting
PAL F2 00 Inverter duty setting
PAL F3 BD Dimmer frequency setting, lower level
PAL F4 00 Dimmer frequency setting, upper level
PAL F5 00 Dimmer PWM setting, lower level
PAL F6 00 Dimmer PWM setting, upper level
PAL F7 00 OFL 1/2 phase
PAL 14 02 System clock setting
CLOSED CAPTION 15 Closed caption threshold level
CCD ISO 16 Closed caption phase setting
AIR SERCH 1,600 Last sync ID frequency at air ON search
20
LC-20B2UA
LC-20B2UB
Page Item
Initial setting
Function Adjust/modify
Gradation & COM settings
18 V255 255 Gradation power reference voltage
V255 BIAS 127 Gradation power reference voltage
V235 222 Gradation power reference voltage
V235 BIAS 127 Gradation power reference voltage
V176 129 Gradation power reference voltage Change it to "130".
V176 BIAS 150 Gradation power reference voltage
V112 96 Gradation power reference voltage
V112 BIAS 170 Gradation power reference voltage
V64 65 Gradation power reference voltage
V64 BIAS 40 Gradation power reference voltage
V32 72 Gradation power reference voltage
V32 BIAS 100 Gradation power reference voltage
19 V21 43 Gradation power reference voltage Change it to "45".
V21 BIAS 50 Gradation power reference voltage
V17 52 Gradation power reference voltage
V17 BIAS 145 Gradation power reference voltage
V7 27 Gradation power reference voltage
V7 BIAS 65 Gradation power reference voltage
V0 0 Gradation power reference voltage
V0 BIAS 80 Gradation power reference voltage
VGL ADJ 27 VGL bias setting
VGL COM 215 VGL COM setting
COM 179 COM amplitude setting
G/A READDATA 00 00 Controller read data setting
G/A READDATA WAIT Read execution
Three-dimensional settings & sync ID settings
20 3D Y/C 2 3D ON/OFF setting
3D Y/C DATA 000000 3D YC data write & read
3D Y/C DATA WAIT Write & read execution
LSYNC 625 Sync ID threshold level (TV)
HSYNC 655 Sync ID threshold level (TV)
AVSYNC 5000 Sync ID threshold level (external input)
VPC FP20H DATA0000 VPC data read value
VPC FP21H DATA0000 VPC data read value
VPC FP13H DATA0000 VPC data read value
MSP DEMO200H DATA0000 MSP data read value
L ERROR WAIT 15s Lamp error detect wait time
L ERROR H TIME 1.0s Lamp error detect time
VPC I2C 20H 24 Sync control setting
Power off mode settings
21 DENKA PORT OFF Power off mode setting
DENKA TESTP 00 Power off mode setting
DENKA TESTP2 30ms Power off mode setting
REMOCON CODE 000 Received remote control code display
21
LC-20B2UA
No or Wrong
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 (10), (11), (13),
(15) and (17) 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 (71) and (72)
Component … Pins (4), (5), (6)
and (75)
Check the IC801 signal
input line.
Check IC801 and its
peripheral circuits.
No
No
No
No
Yes
Yes
Yes
Yes
LC-20B2UB
TROUBLE SHOOTING TABLE
No
INCH SIZE 20
MODEL B2UA
SYSTEM N358
Go to the adjustment process mode.
1
NTSC PWM FREQ OCO
No Power (Power LED indicator still in red)
PAL PWM FREQ OBD
NTSC PWM DUTY 0
B2UA VER 1.xx
PAL PWM DUTY 0
TV GAIN OFF
ERROR NO RESET 5
V-CHIP 1
CANADIAN VCHIP OFF
Move the cursor to ERROR NO RESET
and click on it (to reset to zero).
Turn off the power.
Is the power turned on again?
F6704, D6700, D6701, Q6700, Q6701, Q6702, Q6703, Q6704, Q6705, Q6706,
Q6707, Q6708, Q6709, Q6710, Q6711, Q6712, Q6713, Q6714 and their
peripheral parts as well as pin (34) of IC1201
D3602, D3603, D3604, D3605, D3606, D3607, Q3600, Q3601, Q3602, Q3603,
Q3604 and their peripheral parts as well as pin (42) of IC2001
Check the following points.
(1) Backlight lamp
(2) Inverter circuit (inverter PWB and main PWB)F6700, F6701, F6702, F6703,
(3) Lamp error detection circuit (terminal PWB and main PWB)D3600, D3601,
This model is equipped with the lamp error detection function that detects the current
flowing into the fluorescent lamp and protects the backlight lamp drive circuit.
If a lamp error is detected, the microprocessor interrupts the unit and the ERROR NO
RESET setting will go up.
When the ERROR NO RESET setting has reached "5", the microprocessor turns and
keeps off the unit's power. To resume the power, take the above procedure to clear the
Note:
ERROR NO RESET setting.
22
Check all the settings on the microprocessor
’s adjust process menu.
No picture
No picture
at all
Yes
No
Are inputs
and outputs
of IC801 as
specified?
Does the LCD
controller test
pattern
appear?
Does the
video decoder
test pattern
appear?
Check IC402
and its
peripheral
parts.
Check
IC1201, its
peripheral
circuits and
the LCD
panel.
Check IC801
and its
peripheral
circuits.
Yes
No
No
No VIDEO
1 or 2
output
Yes
No
Are inputs
and outputs
of IC402 as
specified?
Check IC402
and its
peripheral
parts.
Check
IC7001 and
its peripheral
parts.
No
Is input at Pin
(73) of IC801
as specified?
Check IC801,
AV1 line and
their
peripheral
parts.
Yes
No
Are input and
output of
IC7001 as
specified?
Check
IC7202 and
its peripheral
parts.
Yes
No
Are input and
output of
IC7202 as
specified?
No
Are pin
(67) of
IC2001
at “H”?
No S
VIDEO
output
Yes
Yes
Are pins (2)
and (12) of
IC7101 60th
at “H”?
No
Are inputs at
Pins (71) and
(72) of IC801
as specified?
Check
SC3405, SY
line, SC line
and peripheral
parts.
No
COMPONENT
output
No
Is input at
Pins (4), (5),
(6) and (75)
of IC801 as
specified?
Check J3404,
DVD-Y line,
PB line, PR
line and
peripheral
parts.
No TV
output
Yes
No
Are voltages
at Pins (6),
(7) and (9) of
tuner as
specified?
Check the
power line.
Yes
No
Is output at
Pin (19) of
tuner as
specified?
Check the
tuner and its
peripheral
parts.
No
Is input at Pin
(3) of IC402
as specified?
Check the
line in
question.
Yes
Check IC402
and its
peripheral
parts.
Yes
No
Are Pins (2)
and (4) of
IC402 at “H”
and “L”
respectively?
Are Pins (65)
and (66) of
IC2001 at “H”
and “L”
respectively?
Yes
Check the
line in
question.
Check pin
(88) of
IC2001 or the
SSW line.
TROUBLE SHOOTING TABLE (Continued)
LC-20B2UA
LC-20B2UB
23
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