Sharp LC-15AV7U User manual

1
LC-15AV7U
S17F1LC15AV7U
SERVICE MANUAL
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 be used.
MODEL
SERVICE MANUAL LCD COLOR TV MODEL LC-15AV7U
LCD COLOR TV
This document has been published to be used for
after sales service only.
The contents are subject to change without notice.
LC-15AV7U
Page
SPECIFICATIONS ............................................................................................................................... 1-1
IMPORTANT SAFEGUARDS AND PRECAUTIONS ........................................................................... 2-1
STANDARD NOTES FOR SERVICING ............................................................................................... 3-1
CABINET DISASSEMBLY INSTRUCTIONS ........................................................................................ 4-1
ELECTRICAL ADJUSTMENT INSTRUCTIONS .................................................................................. 5-1
HOW TO INITIALIZE THE LCD TELEVISION ..................................................................................... 6-1
TROUBLESHOOTING ......................................................................................................................... 7-1
BLOCK DIAGRAMS ............................................................................................................................. 8-1
SCHEMATIC DIAGRAMS/ CBA'S AND TEST POINTS ....................................................................... 9-1
WAVEFORMS .................................................................................................................................... 10-1
WIRING DIAGRAM ............................................................................................................................ 11-1
IC PIN FUNCTION DESCRIPTIONS .................................................................................................. 12-1
EXPLODED VIEWS ........................................................................................................................... 13-1
MECHANICAL PARTS LIST ............................................................................................................... 14-1
ELECTRICAL PARTS LIST ................................................................................................................ 15-1
CONTENTS

1-1 A7121SP
SPECIFICATIONS
<TUNER>
VHF/UHF Input ................... 75ohm Unbal., F type
Intermediate Freq. .............. Picture 45.75 MHz, Sound 41.25 MHZ
Description Condition Unit Nominal Limit
1. Video S/N 80dB
dB
dB ---
---
>43
>45
2. Audio S/N 80dB
<LCD PANEL>
Description Condition Unit Nominal Limit
1. Number of Pixels Vertical
Horizontal
Vertical
Horizontal
pixels
pixels
768
1024 ---
---
---
---
-60 to 60
-50 to 50
2. Viewing Angle ˚
˚
<VIDEO>
Description Condition Unit Nominal Limit
1. Over Scan Vertical
Horizontal %
%
5
5
---
---
---
---
---
---
2. Color Temperature
y
x
AT 80% WHITE FIELD
AT 100% WHITE FIELD
°K
0.278
10500
3. Resolution
±0.005
±0.005
4. Brightness
Vertical
Horizontal line
line
0.286
400
350
350
cd/m2
<AUDIO>
All items are measured across 8Ωload at speaker output terminal with L.P.F.
Description Condition Unit Nominal Limit
1. Audio Output Power 10% THD: Lch/Rch W 1.0/1.0 0.8/0.8
2. Audio Distortion 500mW: Lch/Rch % 1.5/1.5 3.0/3.0
3. Audio Freq. Response
4. Audio S/N VIDEO1
VIDEO2
-6dB: Lch
Hz
Hz
---
---
70 to 8 k
70 to 8 k
-6dB: Rch
dB
dB
---
---
>45/45
>45/45
The LCD panel is manufactured to provide many years of useful life. Occasionally a
few non active pixels may appear as a tiny spec of color. This is not to be consid-
ered a defect in the LCD screen.

1-2 A7121SP
<ATSC>
Description Condition Unit Nominal Limit
1. RECEIVED FREQ. RANGE
5. MULTIPATH
(-28dBm)
2. ATSC DYNAMIC RANGE
(min./max.)
3. ATSC SUSCEPTIBILITY TO
RANDOM NOISE
4. NTSC CO-CHANNEL
INTERFERENCE
6. Audio S/N (0dBfs)
7. Audio DIST. (0dBfs)
+
-
VHF LOW BAND. CH.4
VHF HI BAND. CH.10
VHF HI BAND. CH.10
UHF BAND. CH.41
UHF BAND. CH.41
VHF LOW BAND. CH.4
VHF HI BAND. CH.10
UHF BAND. CH.41
A
B
C
D
E
F
G
Lch
Rch
Lch
Rch
FF
VHF LOW BAND. CH.4
kHz
dBm
dB
dB
dB
dB
%
---
---
---
---
---
---
---
>100
-76/0
<26
>-6
<6
>50
<3
Note:
Nominal specifications represent the design specifications. All units should be able to approximate these. Some will
exceed and some may drop slightly below these specifications. Limit specifications represent the absolute worst
condition that still might be considered acceptable. In no case should a unit fail to meet limit specifications.

2-1 LCVISP
IMPORTANT SAFEGUARDS AND PRECAUTIONS
Safety Precautions for LCD TV Circuit
1. Before returning an instrument to the customer,
always make a safety check of the entire instrument,
including, but not limited to, the following items:
a. Be sure that no built-in protective devices are defective
and have been defeated during servicing.
(1) Protective shields are provided on this chassis to
protect both the technician and the customer.
Correctly replace all missing protective shields,
including any removed for servicing convenience.
(2) When reinstalling the chassis and/or other
assembly in the cabinet, be sure to put back in place
all protective devices, including but not limited to,
nonmetallic control knobs, insulating fishpapers,
adjustment and compartment covers/shields, and
isolation resistor/capacitor networks. Do not operate
this instrument or permit it to be operated without
all protective devices correctly installed and
functioning. Servicers who defeat safety features
or fail to perform safety checks may be liable for
any resulting damage.
b. Be sure that there are no cabinet openings through
which an adult or child might be able to insert their
fingers and contact a hazardous voltage. Such
openings include, but are not limited to, (1) spacing
between the Liquid Crystal Panel and the cabinet
mask, (2) excessively wide cabinet ventilation slots,
and (3) an improperly fitted and/or incorrectly secured
cabinet back cover.
c. Antenna Cold Check - With the instrument AC plug
removed from any AC source, connect an electrical
jumper across the two AC plug prongs. Place the
instrument AC switch in the on position. Connect one
lead of an ohmmeter to the AC plug prongs tied
together and touch the other ohmmeter lead in turn
to each tuner antenna input exposed terminal screw
and, if applicable, to the coaxial connector. If the
measured resistance is less than 1.0 megohm or
greater than 5.2 megohm, an abnormality exists that
must be corrected before the instrument is returned
to the customer. Repeat this test with the instrument
AC switch in the off position.
d. Leakage Current Hot Check - With the instrument
completely reassembled, plug the AC line cord directly
into a 120V AC outlet. (Do not use an isolation
transformer during this test.) Use a leakage current
tester or a metering system that complies with
American National Standards Institute (ANSI) C101.1
Leakage Current for Appliances and Underwriters
Laboratories (UL) 1410, (50.7). With the instrument
AC switch first in the on position and then in the off
Prior to shipment from the factory, our products are strictly inspected for recognized product safety and electrical
codes of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally
important to implement the following precautions when a set is being serviced.
position, measure from a known earth ground (metal
water pipe, conduit, etc.) to all exposed metal parts
of the instrument (antennas, handle brackets, metal
cabinet, screw heads, metallic overlays, control
shafts, etc.), especially any exposed metal parts that
offer an electrical return path to the chassis. Any
current measured must not exceed 0.5 milli-ampere.
Reverse the instrument power cord plug in the outlet
and repeat the test.
_
DEVICE
LEAKAGE
CURRENT
TESTER
ALSO TEST WITH
PLUG REVERSED
USING AC
ADAPTER PLUG
AS REQUIRED
TEST ALL EXPOSED
METAL SURFACES
+
READING SHOULD
NOT BE ABOVE 0.5 mA
EARTH
GROUND
BEING
TESTED
ANY MEASUREMENTS NOT WITHIN THE LIMITS
SPECIFIED HEREIN INDICATE A POTENTIAL
SHOCK HAZARD THAT MUST BE ELIMINATED
BEFORE RETURNING THE INSTRUMENT TO THE
CUSTOMER OR BEFORE CONNECTING THE
ANTENNA OR ACCESSORIES.
2. Read and comply with all caution and safety-related
notes on or inside the receiver cabinet, on the receiver
chassis, or on the Liquid Crystal Panel.
3. Design Alteration Warning - Do not alter or add to
the mechanical or electrical design of this TV receiver.
Design alterations and additions, including, but not
limited to circuit modifications and the addition of
items such as auxiliary audio and/or video output
connections, might alter the safety characteristics of
this receiver and create a hazard to the user. Any
design alterations or additions will void the
manufacturer's warranty and may make you, the
servicer, responsible for personal injury or property
damage resulting therefrom.

2-2 LCVISP
4. Observe original lead dress. Take extra care to
assure correct lead dress in the following areas:a.
near sharp edges,b. near thermally hot parts-be sure
that leads and components do not touch thermally
hot parts,c. the AC supply,d. high voltage, and,e.
antenna wiring. Always inspect in all areas for pinched,
out of place, or frayed wiring. Check AC power cord
for damage.
5. Components, parts, and/or wiring that appear to
have overheated or are otherwise damaged should
be replaced with components, parts, or wiring that
meet original specifications. Additionally, determine
the cause of overheating and/or damage and, if
necessary, take corrective action to remove any
potential safety hazard.
6. Product Safety Notice - Some electrical and
mechanical parts have special safety-related
characteristics which are often not evident from
visual inspection, nor can the protection they give
necessarily be obtained by replacing them with
components rated for higher voltage, wattage, etc..
Parts that have special safety characteristics are
identified by a ( #) on schematics and in parts lists.
Use of a substitute replacement that does not have
the same safety characteristics as the recommended
replacement part might create shock, fire, and/or
other hazards. The product's safety is under review
continuously and new instructions are issued
whenever appropriate. Prior to shipment from the
factory, our products are strictly inspected to confirm
they comply with the recognized product safety and
electrical codes of the countries in which they are to
be sold. However, in order to maintain such
compliance, it is equally important to implement the
following precautions when a set is being serviced.

2-3 LCVISP
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 F601 (4.0A, 125V).
4A/125V
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 120 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 1.5k 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.
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:
• 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.
DVM
AC SCALE
1.5k ohm
10W
TO EXPOSED
METAL PARTS
CONNECT TO
KNOWN EARTH
GROUND
0.15 F
TEST PROBE
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 "#"
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.
SAFETY NOTICE

2-4 LCVISP
AVERTISSEMENT
1. N’entreprendre aucune modification de tout circuit.
C’est dangereux.
2. Débrancher le récepteur avant toute réparation.
PRECAUTION: POUR LA
PROTECTION CONTINUE
CONTRE LES RISQUES
D'INCENDIE, REMPLACER LE
FUSIBLE PAR UN FUSIBLE DE
MEME TYPE F601 (4.0A, 125V).
4A/125V
VERIFICATIONS CONTRE L’INCEN-DIE
ET LE CHOC ELECTRIQUE
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 et de compartiment, les réseaux de
résistance-capacité, 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 prise de courant de 120V. (Ne pas utiliser de
transformateur d’isolation pour cet essai).
• A l’aide de deux fils à pinces, brancher une résistance
de 1.5kΩ10 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
PRECAUTIONS A PRENDRE LORS DE LA REPARATION
Ne peut effectuer la réparation qu’ un technicien spécialisé qui s’est parfaitement
accoutumé à toute vérification de sécurité et aux conseils suivants.
conduite électrique ou une prise de terre branchée à
la terre.
• 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
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.
Toutes 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.
Dans le cas contraire, il y a une possibilité de choc
électrique qui doit être supprimée avant de rendre le
récepteur au client.
DVM
ECHELLE CA
1.5k ohm
10W
0.15 F
SONDE D'ESSAI
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
identifiées par la marque "#" 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.

3-1 LCV_NOTE
NOTE: CBA AND PWB MEANS PRINTED WIRING
BOARD.
Circuit Board Indications
a. The output pin of the 3 pin Regulator ICs is indicated
as shown.
Top View
Out In
Bottom View
Input
b. For other ICs, pin 1 and every fifth pin are indicated
as shown.
5
10
Pin 1
< Bottom View >
c. The 1st pin of every male connector is indicated as
shown.
Pin 1
< Bottom View >
Instructions for Connectors
1. When you connect or disconnect the FFC (Flexible
Foil Connector) cable, be sure to first disconnect the
AC cord.
2. FFC (Flexible Foil Connector) cable should be in-
serted parallel into the connector, not at an angle.
FFC Cable
Connector
CBA
* Be careful to avoid a short circuit.
Precautions for Using Lead-free Solder
1 Employing lead-free solder
Pb free mark (as shown below) indicates lead-free
solder, and is attached on the PWBs and service
manuals. For PWBs with Pb free mark, be sure to use
lead-free solder. For PWB without Pb free mark, use
standard solder. The alphabetical character following
Pb shows the type of lead-free solder.
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.
Lead-free wire solder for servicing
STANDARD NOTES FOR SERVICING
Part No. Description Code
ZHNDAi123250E J 0.3mm 250g(1roll) BL
ZHNDAi126500E J 0.6mm 500g(1roll) BK
ZHNDAi12801KE J 1.0mm 1kg(1roll) BM

3-2 LCV_NOTE
How to Remove / Install Flat Pack-IC
1. Removal
With Hot-Air Flat Pack-IC Desoldering Machine:
(1) Prepare the hot-air flat pack-IC desoldering ma-
chine, then apply hot air to the Flat Pack-IC (about 5
to 6 seconds). (Fig. S-1-1)
Fig. S-1-1
(2) Remove the flat pack-IC with tweezers while apply-
ing the hot air.
(3) Bottom of the flat pack-IC is fixed with glue to the
CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. S-1-6)
(4) Release the flat pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
Caution:
1. Do not supply hot air to the chip parts around the flat
pack-IC for over 6 seconds because damage to the
chip parts may occur. Put masking tape around the
flat pack-IC to protect other parts from damage.
(Fig. S-1-2)
2. The flat pack-IC on the CBA is affixed with glue, so
be careful not to break or damage the foil of each pin
or the solder lands under the IC when removing it.
Hot-air
Flat Pack-IC
Desoldering
Machine
CBA
Flat Pack-IC
Tweezers
Masking
Tape
Fig. S-1-2
With Soldering Iron:
(1) Using desoldering braid, remove the solder from all
pins of the flat pack-IC. When you use solder flux
which is applied to all pins of the flat pack-IC, you can
remove it easily. (Fig. S-1-3)
Flat Pack-IC Desoldering Braid
Soldering Iron
Fig. S-1-3
(2) Lift each lead of the flat pack-IC upward one by one,
using a sharp pin or wire to which solder will not
adhere (iron wire). When heating the pins, use a fine
tip soldering iron or a hot air desoldering machine.
(Fig. S-1-4)
Fine Tip
Soldering Iron
Sharp
Pin
Fig. S-1-4
(3) Bottom of the flat pack-IC is fixed with glue to the
CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. S-1-6)
(4) Release the flat pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
With Iron Wire:
(1) Using desoldering braid, remove the solder from all
pins of the flat pack-IC. When you use solder flux
which is applied to all pins of the flat pack-IC, you can
remove it easily. (Fig. S-1-3)
(2) Affix the wire to a workbench or solid mounting point,
as shown in Fig. S-1-5.
(3) While heating the pins using a fine tip soldering iron
or hot air blower, pull up the wire as the solder melts
so as to lift the IC leads from the CBA contact pads
as shown in Fig. S-1-5.

3-3 LCV_NOTE
(4) Bottom of the flat pack-IC is fixed with glue to the
CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. S-1-6)
(5) Release the flat pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
Note:
When using a soldering iron, care must be taken to
ensure that the flat pack-IC is not being held by glue.
When the flat pack-IC is removed from the CBA,
handle it gently because it may be damaged if force
is applied.
To Solid
Mounting Point
Soldering Iron
Iron Wire
or
Hot Air Blower
Fig. S-1-5
Fine Tip
Soldeing Iron
CBA
Flat Pack-IC
Tweezers
Fig. S-1-6
2. Installation
(1) Using desoldering braid, remove the solder from the
foil of each pin of the flat pack-IC on the CBA so you
can install a replacement flat pack-IC more easily.
(2) The “ ” mark on the flat pack-IC indicates pin 1. (See
Fig. S-1-7.) Be sure this mark matches the 1 on the
PCB when positioning for installation. Then presol-
der the four corners of the flat pack-IC. (See Fig. S-
1-8.)
(3) Solder all pins of the flat pack-IC. Be sure that none
of the pins have solder bridges.
Example :
Pin 1 of the Flat Pack-IC
is indicated by a " " mark. Fig. S-1-7
Presolder
CBA
Flat Pack-IC
Fig. S-1-8

3-4 LCV_NOTE
Instructions for Handling
Semi-conductors
Electrostatic breakdown of the semi-conductors may
occur due to a potential difference caused by electrostatic
charge during unpacking or repair work.
1. Ground for Human Body
Be sure to wear a grounding band (1MΩ) that is properly
grounded to remove any static electricity that may be
charged on the body.
2. Ground for Workbench
Be sure to place a conductive sheet or copper plate with
proper grounding (1MΩ) on the workbench or other
surface, where the semi-conductors are to be placed.
Because the static electricity charge on clothing will not
escape through the body grounding band, be careful to
avoid contacting semi-conductors with your clothing.
CBA
< Incorrect >
CBA
Grounding Band
Conductive Sheet or
Copper Plate
< Correct >

4-1 A7121DC
NOTE: CBA AND PWB MEANS PRINTED WIRING
BOARD.
1. Disassembly Flowchart
This flowchart indicates the disassembly steps for the
cabinet parts, and the CBA in order to gain access to
item(s) to be serviced. When reassembling, follow the
steps in reverse order. Bend, route and dress the cables
as they were.
[3] Rear Cabinet
[2] Stand Cover
[1] Arm Assembly
[5] Tilt Stand
Holder
[7] Jack Holder
[8] DTV Module
CBA Unit
[6] IR Sensor
CBA
[4] Function CBA
[9] Main CBA
[10] LCD Holder
[11] LVDS CBA
Unit
[12] LCD Module
[16] Front Cabinet
[17] Front Cover
[15] Speaker (s)
[13] Junction-A
CBA
[14] Junction-B
CBA
2. Disassembly Method
Step/
Loc.
No.
Part
Removal
Fig.
No.
Remove/*Unhook/
Unlock/Release/
Unplug/Unclamp/
Desolder
Note
[1] Arm
Assembly D1 2(S-1), 6(S-2) ---
[2] Stand
Cover D1 --------------- ---
[3] Rear
Cabinet D1 10(S-3), (S-4) ---
[4] Function
CBA
D2
D3 5(S-5) ---
[5] Tilt Stand
Holder D2 2(S-6) ---
, CL1107
*
CABINET DISASSEMBLY INSTRUCTIONS
(
1
)(
2
)(
3
)(
4
)(
5
)
Step/
Loc.
No.
Part
Removal
Fig.
No.
Remove/*Unhook/
Unlock/Release/
Unplug/Unclamp/
Desolder
Note
[6] IR Sensor
CBA
D2
D3 (S-7), ---
[7] Jack Holder D2 (S-8) ---
*CL1104
[8]
DTV
Module
CBA Unit
D2
D4
7(S-9), *CL801,
*CL802, *CN61,
*CN62, *CN401,
*CN403, *CN1201,
*CN1202, Module
PCB Holder
---
[9] Main CBA D2
D4 --------------- ---
[10] LCD Holder D2 5(S-10), 4(S-11) ---
[11] LVD S CBA
Unit
D2
D4 3(S-12), *CN1411 ---
[12] LCD
Module D2 --------------- ---
[13] Junction-A
CBA D2 Desolder ---
[14] Junction-B
CBA D2 Desolder ---
[15] Speaker (s) D2 4(S-13), Speaker
Holder (s) ---
[16] Front
Cabinet D2 --------------- ---
[17] Front Cover D2 --------------- ---
Note:
(1) Order of steps in procedure. When reassembling, follow
the steps in reverse order. These numbers are also used
as the Identification (location) No. of parts in figures.
(2) Parts to be removed or installed.
(3) Fig. No. showing procedure of part location
(4) Identification of parts to be removed, unhooked, un-
locked, released, unplugged, unclamped, or desoldered.
P = Spring, L = Locking Tab, S = Screw,
CN = Connector
* = Unhook, Unlock, Release, Unplug, or Desolder
e.g. 2(S-2) = two Screws (S-2),
2(L-2) = two Locking Tabs (L-2)
(5) Refer to the following "Reference Notes in the Table."

4-2 A7121DC
Fig. D1
[3] Rear Cabinet
[1] Arm Assembly
(S-3)
(S-4)
(S-3)
(S-1)
[2] Stand Cover
(S-2) (S-2)
(S-3)
(S-3)

4-3 A7121DC
[7] Jack
Holder
[10] LCD Holder
[4] Function CBA
[6] IR Sensor CBA
[17] Front Cover
[15] Speaker
[15] Speaker
[5] Tilt Stand
Holder
(S-6)
(S-7)
(S-5)
[11] LVDS CBA Unit
[9] Main CBA
(S-9)
(S-10)
(S-10)
(S-11)
(S-12)
(S-5)
[8] DTV Module
CBA Unit
Module PCB
Holder
[12] LCD Module
[16] Front Cabinet
(S-9)
(S-8)
(S-9)
(S-9)
(S-10)
(S-10)
(S-11)
(S-11)
(S-11)
(S-5)
(S-9)
[14] Junction-B
CBA
Fig. D2
Speaker
Holder
(S-13)
Desolder
Speaker
Holder
(S-13)
[13] Junction-A CBA
Desolder

4-4 A7121DC
CN802
Fig. D3
CL1104
CN1201
CN1202
CN1301
CN401
CN403
To
LCD
Module
Main CBA
CN1302
IR Sensor CBA
CN62 CN61
CN101
CN102
DTV Module CBA Unit
CL1107
Function CBA
CN1411
CN1401CN1402
To LCD Module
LVDS CBA
Unit
To
Speaker
CL801
Junction-A
CBA
To Speaker
CL802
Junction-B
CBA
CN801
TV Cable Wiring Diagram

5-1 A7121EA
NOTE: CBA AND PWB MEANS PRINTED WIRING
BOARD."
NOTE:
Electrical adjustments are required after replacing circuit
components and certain mechanical parts. It is important
to perform these adjustments only after all repairs and
replacements have been completed.
Also, do not attempt these adjustments unless the
proper equipment is available.
Test Equipment Required
1. DC Voltmeter
2. NTSC Pattern Generator (Color Bar W/White Win-
dow, Red Color, Dot Pattern, Gray Scale, Monoscope,
Multi-Burst)
3. Remote control unit
4. Color Analyzer
How to enter the service mode:
Press [MENU] and [POWER] buttons on the TV unit
simultaneously in the standby mode.
1. Initial Setting
General : Enter service mode.
Set initial data as shown on table 1.
Press the number after [MENU] on the table to access
next item. Press [CH. o/ p] to change data value.
Table 1: Initial Data
VALUE
DATA
[1]
[2]
RF-BRT
[MENU]
122
RF-CNT 200
RF-CLR-R 130
RF-CLR-B 115
RF-TNT 135
RF-SHR
123V-BRT
[MENU]
112
V-CNT 182
V-CLR-R 110
V-CLR-B 110
V-TNT 138
V-SHR 112
ITEM (on the
remote control)
BUTTON
ELECTRICAL ADJUSTMENT INSTRUCTIONS
ITEM VALUE
DATA
COR(C/D1)
[VOL -] [1]
[VOL -] [3]
[VOL -] [4]
[VOL -] [6]
128
C-COR(C/D2)128
COB(C/D1)128
C-COB(C/D2)128
DR(C/D1)128
C-DR(C/D2)128
DB(C/D1)128
C-DB(C/D2)128
[6]
[7]
123D3-BRT
[MENU]
D3-CNT 170
D3-CLR-R 100
D3-CLR-B 100
D3-TNT 120
D3-SHR 112
DT-BRT
[MENU]
128
DT-CNT 200
DT-CLR-R 100
DT-CLR-B 100
DT-TNT 140
DT-SHR 112
[4]
[5]
115D1-BRT
[MENU]
D1-CNT 182
D1-CLR-R 127
D1-CLR-B 125
D1-TNT 140
D1-SHR 112
D2-BRT
[MENU]
134
D2-CNT 165
D2-CLR-R 121
D2-CLR-B 121
D2-TNT 135
D2-SHR 112
[3]
S-BRT
[MENU]
123
S-CNT 182
S-CLR-R 130
S-CLR-B 120
S-TNT 135
S-SHR 112
(on the
remote control)
BUTTON

5-2 A7121EA
The following adjustment normally are not attempted
in the field. Only when replacing the LCD Panel then
adjust as a preparation.
2. White Balance Adjustment
Purpose: To mix red, green and blue beams correctly for
pure white.
Symptom of Misadjustment: White becomes bluish or
reddish.
Test point Adj. Point Mode Input
Screen
M. EQ. Spec.
Pattern Generator,
Color Analyzer
Figure
[RF/INPUT1]
C/D1
[INPUT2]
C/D2
White Purity
(APL 80%)
or
(APL 20%)
x (0.273 to 0.283)
y (0.281 to 0.291)
VOL -
buttons
Color Analyzer
It carries out in a darkroom.
L = 3 cm
Perpendicularity
INPUT: WHITE 80%, 20%
1. Operate the unit for more than 20 minutes.
2. Input the White Purity.
3. Set the color analyzer to the CHROMA mode and
bring the optical receptor to the center on the LCD-
Panel surface after zero point calibration as shown
above.
Note: The optical receptor must be set perpendicu-
larly to the LCD Panel surface.
4. [RF/INPUT1]
Enter the service mode. Press [VOL -] button on the
remote control unit and select "C/D1" mode.
[INPUT2]
Enter the service mode. Press [VOL -] button on the
remote control unit and select "C/D2" mode.
5. [RF/INPUT1]----(APL80%)
Press [6] button to select "DB(C/D1)" for Blue adjust-
ment. Press [4] button to select "DR(C/D1)" for Red
adjustment. When "x" value and "y" value are not
within specification, adjust "DB (C/D1)" or "DR (C/
D1)" or "DR (C/D1)". Refer to "1. Initial Setting."
[RF/INPUT1]----(APL20%)
Press [3] button to select "COB(C/D1)" for Blue
adjustment. Press [1] button to select "COR(C/D1)"
for Red adjustment. When "x" value and "y" value are
not within specification, adjust "COB (C/D1)" or "COR
(C/D1)". Refer to "1. Initial Setting."
6. [INPUT2]----(APL80%)
Press [6] button to select "C-DB(C/D2)" for Blue
adjustment. Press [4] button to select "C-DR(C/D2)"
for Red adjustment.When "x" value and "y" value are
not within specification, adjust "C-DB(C/D2)" or "C-
DR(C/D2)". Refer to "1. Initial Setting."
[INPUT2]----(APL20%)
Press [3] button to select "C-COB(C/D2)" for Blue
adjustment. Press [1] button to select "C-COR(C/
D2)" for Red adjustment.When "x" value and "y" value
are not within specification, adjust "C-COB(C/D2)" or
"C-COR(C/D2)".
Refer to "1. Initial Setting."
7. Turn the power off and on again. (Main power button
on the TV unit.)
3. Sub-Brightness Adjustment
Purpose: To get proper brightness.
Symptom of Misadjustment: If Sub-Brightness is
incorrect, proper brightness cannot be obtained by
adjusting the Brightness Control.
Adj. Point Input
M. EQ. Spec.
Pattern
Generator
Figure
Ant.input, Any channel,
SMPTE pattern,
[RF/INPUT1]: CG-931 (KENWOOD),
[INPUT2]: CG-931 (KENWOOD),
w/SETUP 7.5IRE
See below
[MENU]
button
White
Black
C positionB position
A position
1. Enter the service mode. Then input above signal.
2. [RF/INPUT1]
Press [MENU] button on the remote control unit and
press [1] on the remote control unit. (selecting "BRT"
mode).

5-3 A7121EA
[INPUT2]
Press [MENU] button on the remote control unit and
press [3] on the remote control unit. (selecting "D1-
BRT" mode).
3. Make sure that contrast and brightness controls are
set to initial position.
4. Confirm "C" position was beginning to bright.
5. If "C" position was beginning to bright, no need to
adjust.
6. If "C" position is not available or to be highly bright-
ness, then adjust IIC-BUS dada.
[RF/INPUT1]: BRT
[INPUT2]: D1-BRT
7. Turn the power off and on again. (Main power button
on the TV unit.)

6-1 A7121INT
1. To enter the service mode, press [MENU] and
[POWER] buttons on the TV unit simultaneously in
the standby mode.
2. To initialize the LCD television, press [DISPLAY]
button on the remote control unit.
3. Confirm "FF" indication on the upper right of the
screen.
HOW TO INITIALIZE THE LCD TELEVISION

7-1 A7121TS
TROUBLESHOOTING
Table of Contents for the Troubleshooting Flow Charts
No.
Chart
Flow
Description Page
1 The power cannot be turned on. 7-2
2 The fuse blows out. 7-2
3 When the output voltage fluctuates. 7-2
4 When buzz sound can be heard in the vicinity of power circuit. 7-2
5+35V is not output. 7-2
6VT+33V is not output. 7-3
7INV+22V is not output. 7-3
8DTV-ON+3.3V is not output. 7-3
9DTV-ON+2.5V is not output. 7-3
10 PANEL+3.3V is not output. 7-3
11 DTV-ON+5V is not output. 7-4
12 AL+3.3V(D) is not output. 7-4
13 AL+1.2V(D) is not output. 7-4
14 AL+3.3V(A) is not output. 7-4
15 P-ON+5V(1) is not output. 7-5
16 +12V is not output. 7-5
17 P-ON+9V is not output. 7-5
18 DTV-ON+1.8V is not output. 7-5
19 The key operation is not functioning. 7-6
20 No operation is possible from the remote control unit. 7-6
21
Picture does not appear normally. (Tuner input (Analog) / Video input/S-Video input) 7-7
22 Picture does not appear normally. (Tuner input (Digital)) 7-7
23 Picture does not appear normally. (Y / Pb / Pr input) 7-7
24 Audio is not outputted normally. (Tuner input) 7-8
25 Audio is not outputted normally. (Tuner input (Digital)) 7-8
26 Audio is not outputted normally. (Audio input terminals) 7-9
NOTE: CBA AND PWB MEANS PRINTED WIRING BOARD.