LG 55LV355C-UA User manual

LED LCD TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : LA0AC
MODEL : 55LV355C 55LV355C-UA
North/Latin America http://aic.lgservice.com
Europe/Africa http://eic.lgservice.com
Asia/Oceania http://biz.lgservice.com
Internal Use Only
Printed in KoreaP/NO : MFL67234710(1109-REV00)

LGE Internal Use OnlyCopyright LG Electronics. Inc. All right reserved.
Only for training and service purposes
- 2 -
CONTENTS
CONTENTS ............................................................................................................................... 2
SAFETY PRECAUTIONS ...........................................................................................................3
SPECIFICATION.........................................................................................................................6
ADJUSTMENT INSTRUCTION ................................................................................................10
TROUBLESHOOTING GUIDE .................................................................................................15
BLOCK DIAGRAM ...................................................................................................................25
EXPLODED VIEW ..................................................................................................................26
SCHEMATIC CIRCUIT DIAGRAM ..............................................................................................

LGE Internal Use OnlyCopyright LG Electronics. Inc. All right reserved.
Only for training and service purposes
- 3 -
SAFETY PRECAUTIONS
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the
Schematic Diagram and Exploded View.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent
Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
General Guidance
An isolation Transformer should always be used during the
servicing of a receiver whose chassis is not isolated from the AC
power line. Use a transformer of adequate power rating as this
protects the technician from accidents resulting in personal injury
from electrical shocks.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitry that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.
When replacing a high wattage resistor (Oxide Metal Film Resistor,
over 1W), keep the resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Before returning the receiver to the customer,
always perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc., to
be sure the set is safe to operate without damage of electrical
shock.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source, connect an
electrical jumper across the two AC plug prongs. Place the AC
switch in the on position, connect one lead of ohm-meter to the AC
plug prongs tied together and touch other ohm-meter lead in turn to
each exposed metallic parts such as antenna terminals, phone
jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩand 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter
with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC voltage
measurements for each exposed metallic part. Any voltage
measured must not exceed 0.75 volt RMS which is corresponds to
0.5mA.
In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Leakage Current Hot Check circuit
1.5 Kohm/10W
To Instrument's
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
IMPORTANT SAFETY NOTICE
0.15uF

LGE Internal Use OnlyCopyright LG Electronics. Inc. All right reserved.
Only for training and service purposes
- 4 -
CAUTION: Before servicing receivers covered by this service
manual and its supplements and addenda, read and follow the
SAFETY PRECAUTIONS on page 3 of this publication.
NOTE: If unforeseen circumstances create conflict between the
following servicing precautions and any of the safety precautions on
page 3 of this publication, always follow the safety precautions.
Remember: Safety First.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power
source before;
a. Removing or reinstalling any component, circuit board
module or any other receiver assembly.
b. Disconnecting or reconnecting any receiver electrical plug or
other electrical connection.
c. Connecting a test substitute in parallel with an electrolytic
capacitor in the receiver.
CAUTION: A wrong part substitution or incorrect polarity
installation of electrolytic capacitors may result in an
explosion hazard.
2. Test high voltage only by measuring it with an appropriate high
voltage meter or other voltage measuring device (DVM,
FETVOM, etc) equipped with a suitable high voltage probe.
Do not test high voltage by "drawing an arc".
3. Do not spray chemicals on or near this receiver or any of its
assemblies.
4. Unless specified otherwise in this service manual, clean
electrical contacts only by applying the following mixture to the
contacts with a pipe cleaner, cotton-tipped stick or comparable
non-abrasive applicator; 10% (by volume) Acetone and 90% (by
volume) isopropyl alcohol (90%-99% strength)
CAUTION: This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of
contacts in not required.
5. Do not defeat any plug/socket B+ voltage interlocks with which
receivers covered by this service manual might be equipped.
6. Do not apply AC power to this instrument and/or any of its
electrical assemblies unless all solid-state device heat sinks are
correctly installed.
7. Always connect the test receiver ground lead to the receiver
chassis ground before connecting the test receiver positive
lead.
Always remove the test receiver ground lead last.
8. Use with this receiver only the test fixtures specified in this
service manual.
CAUTION: Do not connect the test fixture ground strap to any
heat sink in this receiver.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid-state) devices can be damaged easily
by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES
devices are integrated circuits and some field-effect transistors and
semiconductor "chip" components. The following techniques
should be used to help reduce the incidence of component
damage caused by static by static electricity.
1. Immediately before handling any semiconductor component or
semiconductor-equipped assembly, drain off any electrostatic
charge on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed to
prevent potential shock reasons prior to applying power to the
unit under test.
2. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such as
aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES
devices.
4. Use only an anti-static type solder removal device. Some solder
removal devices not classified as "anti-static" can generate
electrical charges sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective
package until immediately before you are ready to install it.
(Most replacement ES devices are packaged with leads
electrically shorted together by conductive foam, aluminum foil
or comparable conductive material).
7. Immediately before removing the protective material from the
leads of a replacement ES device, touch the protective material
to the chassis or circuit assembly into which the device will be
installed.
CAUTION: Be sure no power is applied to the chassis or circuit,
and observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Otherwise harmless motion such as
the brushing together of your clothes fabric or the lifting of your
foot from a carpeted floor can generate static electricity
sufficient to damage an ES device.)
General Soldering Guidelines
1. Use a grounded-tip, low-wattage soldering iron and appropriate
tip size and shape that will maintain tip temperature within the
range or 500°F to 600°F.
2. Use an appropriate gauge of RMA resin-core solder composed
of 60 parts tin/40 parts lead.
3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use a mall wire-
bristle (0.5 inch, or 1.25cm) brush with a metal handle.
Do not use freon-propelled spray-on cleaners.
5. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.
(500°F to 600°F)
b. Heat the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction-
type solder removal device or with solder braid.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
6. Use the following soldering technique.
a. Allow the soldering iron tip to reach a normal temperature
(500°F to 600°F)
b. First, hold the soldering iron tip and solder the strand against
the component lead until the solder melts.
c. Quickly move the soldering iron tip to the junction of the
component lead and the printed circuit foil, and hold it there
only until the solder flows onto and around both the
component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit
board printed foil.
d. Closely inspect the solder area and remove any excess or
splashed solder with a small wire-bristle brush.
SERVICING PRECAUTIONS

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- 5 -
IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong) through
which the IC leads are inserted and then bent flat against the
circuit foil. When holes are the slotted type, the following technique
should be used to remove and replace the IC. When working with
boards using the familiar round hole, use the standard technique
as outlined in paragraphs 5 and 6 above.
Removal
1. Desolder and straighten each IC lead in one operation by gently
prying up on the lead with the soldering iron tip as the solder
melts.
2. Draw away the melted solder with an anti-static suction-type
solder removal device (or with solder braid) before removing the
IC.
Replacement
1. Carefully insert the replacement IC in the circuit board.
2. Carefully bend each IC lead against the circuit foil pad and
solder it.
3. Clean the soldered areas with a small wire-bristle brush.
(It is not necessary to reapply acrylic coating to the areas).
"Small-Signal" Discrete Transistor
Removal/Replacement
1. Remove the defective transistor by clipping its leads as close as
possible to the component body.
2. Bend into a "U" shape the end of each of three leads remaining
on the circuit board.
3. Bend into a "U" shape the replacement transistor leads.
4. Connect the replacement transistor leads to the corresponding
leads extending from the circuit board and crimp the "U" with
long nose pliers to insure metal to metal contact then solder
each connection.
Power Output, Transistor Device
Removal/Replacement
1. Heat and remove all solder from around the transistor leads.
2. Remove the heat sink mounting screw (if so equipped).
3. Carefully remove the transistor from the heat sink of the circuit
board.
4. Insert new transistor in the circuit board.
5. Solder each transistor lead, and clip off excess lead.
6. Replace heat sink.
Diode Removal/Replacement
1. Remove defective diode by clipping its leads as close as
possible to diode body.
2. Bend the two remaining leads perpendicular y to the circuit
board.
3. Observing diode polarity, wrap each lead of the new diode
around the corresponding lead on the circuit board.
4. Securely crimp each connection and solder it.
5. Inspect (on the circuit board copper side) the solder joints of
the two "original" leads. If they are not shiny, reheat them and if
necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
1. Clip each fuse or resistor lead at top of the circuit board hollow
stake.
2. Securely crimp the leads of replacement component around
notch at stake top.
3. Solder the connections.
CAUTION: Maintain original spacing between the replaced
component and adjacent components and the circuit board to
prevent excessive component temperatures.
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit
board will weaken the adhesive that bonds the foil to the circuit
board causing the foil to separate from or "lift-off" the board. The
following guidelines and procedures should be followed whenever
this condition is encountered.
At IC Connections
To repair a defective copper pattern at IC connections use the
following procedure to install a jumper wire on the copper pattern
side of the circuit board. (Use this technique only on IC
connections).
1. Carefully remove the damaged copper pattern with a sharp
knife. (Remove only as much copper as absolutely necessary).
2. carefully scratch away the solder resist and acrylic coating (if
used) from the end of the remaining copper pattern.
3. Bend a small "U" in one end of a small gauge jumper wire and
carefully crimp it around the IC pin. Solder the IC connection.
4. Route the jumper wire along the path of the out-away copper
pattern and let it overlap the previously scraped end of the good
copper pattern. Solder the overlapped area and clip off any
excess jumper wire.
At Other Connections
Use the following technique to repair the defective copper pattern
at connections other than IC Pins. This technique involves the
installation of a jumper wire on the component side of the circuit
board.
1. Remove the defective copper pattern with a sharp knife.
Remove at least 1/4 inch of copper, to ensure that a hazardous
condition will not exist if the jumper wire opens.
2. Trace along the copper pattern from both sides of the pattern
break and locate the nearest component that is directly
connected to the affected copper pattern.
3. Connect insulated 20-gauge jumper wire from the lead of the
nearest component on one side of the pattern break to the lead
of the nearest component on the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed so the
it does not touch components or sharp edges.

LGE Internal Use OnlyCopyright LG Electronics. Inc. All right reserved.
Only for training and service purposes
1. Application range
This spec sheet is applied LCD TV with LA0AC chassis.
2. Requirement for Test
Each part is tested as below without special appointment.
1) Temperature: 25 ºC ± 5 ºC
2) Relative Humidity: 65 ± 10 %
3) Power Voltage : Standard input voltage(100-240V~, 50/60Hz)
* Standard Voltage of each product is marked by models
4) Specification and performance of each parts are followed each drawing and specification by part number in accordance with
BOM.
5) The receiver must be operated for about 5 minutes prior to the adjustment.
3. Test method
1) Performance: LGE TV test method followed
2) Demanded other specification
- Safety : UL, CSA, IEC specification
- EMC: FCC, ICES, IEC specification
- 6 -
SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement.
4. General Specification(TV)
No Item Specification Remark
1 Receivable System 1) ATSC / NTSC-M
2 Available Channel 1) VHF : 02 ~ 13
2) UHF : 14 ~ 69
3) DTV : 02 ~ 69
4) CATV : 01 ~ 135
5) CADTV : 01 ~ 135
3 Input Voltage 1) AC 100 - 240V~ 50/60Hz Mark : 110V, 60Hz (N.America)
4 Market North America
5 Screen Size 22 inch Wide (1920x1080) FHD + 60Hz 22LV255C-UA_AUO
26 inch Wide (1366x768) HD + 60Hz 26LV255C-UA_AUO
42 inch Wide (1920x1080) FHD + 60Hz 42LV355C-UA_LGD
55 inch Wide (1920x1080) FHD + 120Hz 55LV355C-UA_LGD
6 Aspect Ratio 16:9
7 Tuning System FS
8 Module AUO(M215HW01-VB) AUO 22LV255C-UA_AUO
AUO(T260XW06-V3) AUO 26LV255C-UA_AUO
LGD(LC420EUN-SDV3) LGD 42LV355C-UA_LGD
LGD(LC550EUF-SDA1) LGD 55LV355C-UA_LGD
9 Operating Environment Temp : 0 ~ 40 deg
Humidity : ~ 80 %
10 Storage Environment Temp : -20 ~ 60 deg
Humidity : -85 %

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5. Chrominance & Luminance (Edge LED models)
No. Item Min Typ Max Unit Remarks
1 White brightness 70 120 cd/m2AUO 22LV255C-UA
100 150 AUO 26LV255C-UA
150 250 LGD 42LV355C-UA
180 250 LGD 55LV355C-UA
2 Luminance uniformity (22 Edge LED) 75 % Full White
Luminance uniformity (26 Edge LED) 77
Luminance uniformity (42 Edge LED) 77
Luminance uniformity (55 Edge LED) 77
3 Color coordinate RED X Typ. 0.635 Typ. 22LV255C-UA (AUO)
(22 Edge LED) Y -0.03 0.349 +0.03
GREEN X 0.332
Y 0.619
BLUE X 0.155
Y 0.055
WHITE X 0.313
Y 0.329
Color coordinate RED X Typ. 0.630 Typ. 26LV255C-UA (AUO)
(26 Edge Y -0.03 0.340 +0.03
LED) GREEN X 0.340
Y 0.620
BLUE X 0.150
Y 0.040
WHITE X 0.280
Y 0.290
Color coordinate RED X Typ. 0.637 Typ. 42LV355C-UA (AUO) )
(42 Edge Y -0.03 0.341 +0.03
LED) GREEN X 0.325
Y 0.600
BLUE X 0.152
Y 0.051
WHITE X 0.279
Y 0.292
Color coordinate RED X Typ. 0.649 Typ. 55LV355C-UA (AUO)
(55 Edge Y -0.03 0.333 +0.03
LED) GREEN X 0.308
Y 0.607
BLUE X 0.150
Y 0.060
WHITE X 0.279
Y 0.292
4 Color coordinate uniformity 0.634 N/A

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No. Item Min Typ Max Unit Remarks
5 Contrast ratio (Module) 600 1000 22LV255C-UA (AUO)
2400 3000 26LV255C-UA (AUO)
1000 1400 42LV355C-UA (AUO)
2400 3000 55LV355C-UA (AUO)
Contrast ratio (DCR) 800,000:1
1,000,000:1 All Global Dimming (Normal Dimming )
6 Color COOL 0.283 0.285 0.287 9300K 22LV255C-UA (AUO)
Temperature 0.291 0.293 0.295
** The W/B Tolerance is ±0.015 for
MEDIUM 0.293 0.295 0.297 8000K picture quality by DQA
0.303 0.305 0.307
WARM 0.311 0.313 0.315 6500K
0.327 0.329 0.331
7 Color COOL 0.254 0.269 0.284 13000K 26LV255C-UA (AUO)
Temperature 0.258 0.273 0.288 42/55LV355C-UA (AUO)
MEDIUM 0.270 0.285 0.300 9300K
** The W/B Tolerance is ±0.015 for
0.278 0.293 0.308 picture quality by DQA
WARM 0.298 0.3130 0.324 6500K
0.314 0.329 0.344
8 Response time 3 9 ms G to G N/A
6. Component Video Input (Y, CB/PB, CR/PR)
No Resolution H-freq(kHz) V-freq.(kHz) Pixel clock Proposed
1. 720*480 15.73 60 13.5135 SDTV ,DVD 480I
2. 720*480 15.73 59.94 13.5 SDTV ,DVD 480I
3. 720*480 31.50 60 27.027 SDTV 480P
4. 720*480 31.47 59.94 27.0 SDTV 480P
5. 1280*720 45.00 60.00 74.25 HDTV 720P
6. 1280*720 44.96 59.94 74.176 HDTV 720P
7. 1920*1080 33.75 60.00 74.25 HDTV 1080I
8. 1920*1080 33.72 59.94 74.176 HDTV 1080I
9. 1920*1080 67.500 60 148.50 HDTV 1080P
10. 1920*1080 67.432 59.94 148.352 HDTV 1080P
11. 1920*1080 27.000 24.000 74.25 HDTV 1080P
12. 1920*1080 26.97 23.976 74.176 HDTV 1080P
13. 1920*1080 33.75 30.000 74.25 HDTV 1080P
14. 1920*1080 33.71 29.97 740176 HDTV 1080P

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7. RGB Input (PC)
No Resolution H-freq(kHz) V-freq.(kHz) Pixel clock Proposed
PC DDC
1. 640*350 31.468 70.09 25.17 EGA X
2. 720*400 31.469 70.08 28.32 DOS O
3. 640*480 31.469 59.94 25.17 VESA(VGA) O
4. 800*600 37.879 60.31 40.00 VESA(SVGA) O
5. 1024*768 48.363 60.00 65.00 VESA(XGA) O
6. 1280*768 47.776 59.870 79.5 CVT(WXGA) X
7. 1360*768 47.712 60.015 85.50 VESA(WXGA) X
8. HDMI input (PC/DTV)
No Resolution H-freq(kHz) V-freq.(kHz) Pixel clock Proposed
PC DDC
1. 640*350 31.468 70.09 25.17 EGA X
2. 720*400 31.469 70.08 28.32 DOS O
3. 640*480 31.469 59.94 25.17 VESA(VGA) O
4. 800*600 37.879 60.31 40.00 VESA(SVGA) O
5. 1024*768 48.363 60.00 65.00 VESA(XGA) O
6. 1280*768 47.776 59.870 79.5 CVT(WXGA) X
7. 1360*768 47.712 60.015 85.50 VESA (WXGA) O
DTV
1 720*480 31.47 60 27.027 SDTV 480P
2 720*480 31.47 59.94 27.00 SDTV 480P
3 1280*720 45.00 60.00 74.25 HDTV 720P
4 1280*720 44.96 59.94 74.176 HDTV 720P
5 1920*1080 33.75 60.00 74.25 HDTV 1080I
6 1920*1080 33.72 59.94 74.176 HDTV 1080I
7 1920*1080 67.500 60 148.50 HDTV 1080P
8 1920*1080 67.432 59.939 148.352 HDTV 1080P
9 1920*1080 27.000 24.000 74.25 HDTV 1080P
10 1920*1080 26.97 23.976 74.176 HDTV 1080P
11 1920*1080 33.75 30.000 74.25 HDTV 1080P
12 1920*1080 33.71 29.97 74.176 HDTV 1080P

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- 10 -
ADJUSTMENT INSTRUCTION
1. Application range
This spec. sheet applies to LA0AC Chassis applied LED LCD
TV all models manufactured in TV factory.
2. Specification
2.1 Because this is not a hot chassis, it is not necessary
to use an isolation transformer. However, the use of
isolation transformer will help protect test instrument.
2.2 Adjustment must be done in the correct order.
2.3 The adjustment must be performed in the
circumstance of 25±5°C of temperature and 65±10%
of relative humidity
2.4 The input voltage of the receiver must keep
100~240V~, 50/60Hz.
2.5 At first Worker must turn on the SET by using Power
Only key.
2.5 The receiver must be operated for about 5 minutes
prior to the adjustment when module is in the
circumstance of over 15.
In case of keeping module is in the circumstance of
0°C, it should be placed in the circumstance of above
15°C for 2 hours
In case of keeping module is in the circumstance of
below -20°C, it should be placed in the circumstance
of above 15°C for 3 hours.
• Caution
When a still image is displayed for 20 minutes or longer
(especially where W/B scale is strong. Digital pattern 13ch
and/or Cross hatch pattern 09ch), there can some
afterimage in the black level area.
3. Adjustment items
3.1 Board Level Adjustment
(1) ADC adjustment: Component 480i, 1080p / RGB-PC 1080p
(2) EDID downloads for HDMI and RGB-PC
• Remark
- Above adjustment items can be also performed in Final
Assembly if needed. Adjustment items in both PCBA and
final assembly stages can be checked by using the
INSTART Menu 1.ADJUST CHECK.
3.2 Final Assembly adjustment
(1) White Balance adjustment
(2) RS-232C functionality check
(3) Factory Option setting per destination
(4) Shipment mode setting (IN-STOP)
3.3 Etc
(1) Ship-out mode
(2) Service Option Default
(3) USB Download(S/W Update, Option, Service only)
(4) ISP Download (Optional)
4. Board Level Adjustment
4.1. ADC Adjustment
4.1.1. Overview
• ADC adjustment is needed to find the optimum black level
and gain in Analog-to-Digital device and to compensate RGB
deviation.
4.1.2. Equipment & Condition
1) Jig (RS-232C protocol)
2) Inner Pattern
- Resolution : 1080p (Inner Pattern)
- Resolution : 1024*768 RGB (Inner Pattern)
- Pattern : Horizontal 100% Color Bar Pattern
- Pattern level : 0.7±0.1 Vp-p
4.1.3. Adjustment
4.1.3.1 Adjustment method
• Using RS-232, adjust items listed in 3.1 in the other
shown in “4.1.3.3”
4.1.3.2 Adj. protocol
Ref.) ADC Adj. RS232C Protocol_Ver1.0
4.1.3.3. Adj. order
• aa 00 00 [Enter ADC adj. mode]
• xb 00 40 [Change input source to Component1(1080i)]
• ad 00 10 [Adjust 480i Comp1]
• xb 00 60 [Change input source to RGB(1024*768)]
• ad 00 10 [Adjust 1024*768 RGB]
• ad 00 90 End adj.
Ref) ADC adj. RS232C Protocol_Ver1.0
Protocol Command SetACK
Enter adj. mode aa 00 00 a 00 OK00x
Source change xb 00 40
xb 00 60
b 00 OK40x (Adjust 480i /1080p Comp1 )
b 00 OK60x (Adjust 1920*1080 RGB)
Begin adj. ad 00 10
Return adj. result OKx (Case of Success)
NGx (Case of Fail)
Read adj. data (main)
ad 00 20
(sub )
ad 00 21
(main)
000000000000000000000000007c007b006dx
(Sub)
000000070000000000000000007c00830077x
Confirm adj. ad 00 99 NG 03 00x (Fai l)
NG 03 01x (Fai l)
NG 03 02x (Fai l)
OK 03 03x (Success)
End adj. aa 00 90 a 00 OK90x

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4.2. EDID/DDC Download
4.2.1 Overview
•It is a VESA regulation. A PC or a MNT will display an
optimal resolution through information sharing without any
necessity of user input. It is a realization of “Plug and Play”.
4.2.2 Equipment
•Since embedded EDID data is used, EDID download JIG,
HDMI cable and D-sub cable are not need.
•Adjust remocon.
4.2.3 Download method
1) Press Adj. key on the Adj. R/C,
2) Select EDID D/L menu.
3) By pressing Enter key, EDID download will begin
4) If Download is successful, OK is display, but If Download is
failure, NG is displayed.
5) If Download is failure, Re-try downloads.
* Caution) When EDID Download, must remove RGB/HDMI
Cable.
4.2.4 EDID DATA
1) North America
# HDMI1-EDID (C/S : 03CC)
EDID Block 0
Block1
# HDMI2-EDID (C/S : 03BC)
Block0
Block1
# RGB-EDID (C/S : 1C)
Block0
5. Final Assembly Adjustment
5.1. White Balance Adjustment
5.1.1. Overview
5.1.1.1. W/B adj. Objective & How-it-works
(1) Objective: To reduce each Panel’s W/B deviation
(2) How-it-works: When R/G/B gain in the OSD is at 192, it
means the panel is at its Full Dynamic Range. In order to
prevent saturation of Full Dynamic range and data, one of
R/G/B is fixed at 192, and the other two is lowered to find
the desired value.
(3) Adj. condition: normal temperature
1) Surrounding Temperature: 25±5°C
2) Warm-up time: About 5 Min
3) Surrounding Humidity: 20% ~ 80%
5.1.2. Equipment
(1) Color Analyzer: CA-210 (NCG: CH 9 / WCG: CH12 / LED:
CH14)
(2) Adj. Computer (During auto adj., RS-232C protocol is
needed)
(3) Adjust Remocon
(4) Video Signal Generator MSPG-925F 720p/204-Gray
(Model: 217, Pattern: 49)
•Color Analyzer Matrix should be calibrated using CS-1000

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5.1.3. Equipment connection
5.1.4. Adjustment Command (Protocol)
(1) RS-232C Command used during auto-adj.
Ex) wb 00 00 -> Begin white balance auto-adj.
wb 00 10 -> Gain adj.
ja 00 ff -> Adj. data
jb 00 c0
...
...
wb 00 1f -> Gain adj. complete
*(wb 00 20(start), wb 00 2f(end)) -> Off-set adj.
wb 00 ff ->End white balance auto adj.
(2) Adj. Map
5.1.5. Adjustment method
5.1.5.1 Auto WB calibration
1) Set TV in adj. mode using POWER ONLY (P-ONLY) key
2) Zero calibrate probe then place it on the center of the
Display
3) Connect Cable(RS-232C)
4) Select mode in adj. Program and begin adj.
5) When adj. is complete (OK Sing), check adj. status pre
mode (Cool, Medium, Warm)
6) Remove probe and RS-232C cable to complete adj.
•W/B Adj. must begin as start command “wb 00 00”, and
finish as end command “wb 00 ff”, and Adj. offset if need
5.1.5.2 Manual adj. method
1) Set TV in Adj. mode using POWER ON
2) Zero Calibrate the probe of Color Analyzer, then place it on
the center of LCD module within 10cm of the surface..
3) Press ADJ key -> EZ adjust using adj. R/C 6. White-
Balance then press the cursor to the right (KEYG). (When
KEY(G) is pressed 204 Gray(80IRE) internal pattern will be
displayed)
4) One of R Gain / G Gain / B Gain should be fixed at 192,
and the rest will be lowered to meet the desired value.
5) Adj. is performed in COOL, MEDIUM, WARM 3 modes of
color temperature.
•If internal pattern is not available, use RF input. In EZ Adj.
menu 6.White Balance, you can select one of 2 Test-pattern:
ON, OFF. Default is inner(ON). By selecting OFF, you can
adjust using RF signal in 204 Gray pattern.
•Adj. condition and cautionary items
1) Lighting condition in surrounding area
Surrounding lighting should be lower 10 lux. Try to isolate
adj. area into dark surrounding.
2) Probe location : Color Analyzer (CA-210) probe should be
within 10cm and perpendicular of the module surface (80°~
100°)
3) Aging time
- After Aging Start, Keep the Power ON status during 5
Minutes.
- In case of LCD, Back-light on should be checked using no
signal or Full-white pattern.
5.1.6 Reference (White Balance Adj. coordinate and color
temperature)
(1) Luminance: 204 Gray, 80IRE
(2) Standard color coordinate and temperature using CS-1000
•Standard color coordinate and temperature using CA-
210(CH 9)
5.2 HDCP (High-Bandwidth Digital
Contents Protection) SETTING
Color Analyzer
Computer
Pattern Generator
RS-232C
RS-232C
RS-232C
Probe
Signal Source
* If TV internal pattern is used, not needed
Connection Diagram of Automatic Adjustment
RS-232C COMMAND
[CMD ID DATA]
Explanation
Wb 00 00 Begin White Balance adj.
Wb 00 ff End White Balance adj. (internal pattern disappears )
Adj. item Command
(lower case ASCII)
Data Range
(Hex.)
Default
(Decimal)
CMD1 CMD2 MIN MAX
R Gain j g 00 C0 172
G Gain j h 00
i 00
C0 172
B Gain j C0 192
R Cut 64
G Cut 64
Cool
B Cut 64
Medium j a 00 C0 192
G Gain j b 00 C0 192
B Gain
R Gain
j c 00 C0 192
R Cut 64
G Cut 64
B Cut 64
R Gain j d 00 C0 192
G Gain j e 00 C0 192
B Gain j f 00 C0 172
R Cut 64
G Cut 64
Warm
B Cut 64
Mode Color Coordination Temp ∆UV
xy
COOL 0.269 0.273 13000K 0.0000
MEDIUM 0.285 0.293 9300K 0.0000
WARM 0.313 0.329 6500K 0.0000
Mode Color Coordination Temp ∆UV
xy
COOL 0.269±0.002 0.273±0.002 13000K 0.0000
MEDIUM 0.285±0.002 0.293±0.002 9300K 0.0000
WARM 0.313+0.002 0.329±0.002 6500K 0.0000

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5.3 Option selection per country
5.3.1 Overview
•Option selection is only done for models in Non-USA North
America due to rating
•Applied model: LA01U Chassis applied None USA
model(CANADA, MEXICO)
5.3.2 Method
(1) Press ADJ key on the Adj. R/C, and then select Country
Group Menu
(2) Depending on destination, select KR or US, then on the
lower Country option, select US, CA, MX. Selection is
done using +, - KEY
5.4 Tool Option selection
•Method: Press Adj. key on the Adj. R/C, then select Tool
option.
6. GND and Hi-pot Test
6.1. Method
6.1.1. GND & HI-POT auto-check preparation
(1) Check the POWER CABLE and SIGNAL CABE
insertion condition
6.1.2. GND & HI-POT auto-check
(1) Pallet moves in the station. (POWER CORD / AV
CORD is tightly inserted)
(2) Connect the AV JACK Tester.
(3) Controller (GWS103-4) on.
(4) GND Test (Auto)
- If Test is failed, Buzzer operates.
- If Test is passed, execute next process (Hi-pot test).
(Remove A/V CORD from A/V JACK BOX)
(5) HI-POT test (Auto)
- If Test is failed, Buzzer operates.
- If Test is passed, GOOD Lamp on and move to next
process automatically.
6.2. Checkpoint
•TEST voltage
- GND: 1.5KV/min at 100mA
- SIGNAL: 3KV/min at 100mA
•TEST time: 1 second
•TEST POINT
- GND TEST = POWER CORD GND & SIGNAL CABLE
METAL GND
- Internal Pressure TEST = POWER CORD GND & LIVE &
NEUTRAL
•LEAKAGE CURRENT: At 0.5mArms
7. EYE-Q Check
Step 1) Turn on the TV.
Step 2) Press EYE button in adjust remote control.
Step 3) Stay 6 seconds with Eye Q sensor hidden located on
the front of the set.
Step 4) Check the “Sensor Data”on the screen and check
whether the value is lower thanafter 6 seconds, the
value does not go below 10, Eye Q sensor is not
working properly. Then, change the sensor.
Step 5) Remove hand from the Eye Q II sensor and stay for 6
seconds.
Step 6) Check whether the “Back Light (xxx)”value has risen
on the screen. If after 6 seconds and the value still
does not go high, the eye Q II sensor is not working
properly. Replace the sensor.
42LV355C -UA 55LV355C - UA
Tool 1 26464 46944
Tool 2 10774 10774
Tool 3 53291 53290
Tool 4 2332 2332
Tool 5 16672 24864
<Step1> <Step2> <Step3>
<Step4> <Step5>

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8. USB S/W Download (Option,
Service only)
1. Put the USB Stick to the USB socket
2. Automatically detecting update file in USB Stick
- If your downloaded program version in USB Stick is Low, it
didn’t work. But your downloaded version is High, USB data
is automatically detecting
3. Show the message “Copying files from memory”
4. Updating is starting.
5. Updating Completed, The TV will restart automatically
6. If your TV is turned on, check your updated version and
Tool option. (Explain the Tool option, next stage)
* If downloading version is more high than your TV have, TV
can lost all channel data. In this case, you have to channel
recover. if all channel data is cleared, you didn’t have a
DTV/ATV test on production line.
* After downloading, have to adjust TOOL OPTION again.
1. Push "IN-START" key in service remote controller.
2. Select "Tool Option 1" and Push “OK”button.
3. Punch in the number. (Each model has their number.)

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TROUBLESHOOTING GUIDE
1. Power-up boot check
Check stand-by Voltage.
P403 9~12pin : +3.5V_ST Check Power connector Main B/D 3.5V Line
Short Check
Check X1002 clock
32 KHz Replace X1002
Check P403 PWR_ON.
1pin : 3.3V Replace Micom(IC1002) or Main board
Check Multi Voltage
P403 2pin:24V or 24V ,17pin:12V
Replace Power Board
Check Inverter Control & Error Out
P403 18 pin : High
P403 24 pin : low
Check Power Board or Module
Check IC402/3/5/7 Output Voltage
IC402 : 2.5V
IC403 : 1.26V
IC405 : 3.3V
IC407 : 1.5V
Replace IC402/ 3 / 5 / 7
Re-download Micom software.
Check Micom Voltage
IC1002 pin 48 : +3.5V Replace L404
Check LVDS Power Voltage
Q409 : 12V Replace Q409
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board
Change Module
ok
ok
ok
ok
ok
ok
ok
ok
ok
okNo
No
No
No
No
No
No
No
No
No
Check X201 Clock
24 MHz Replace X201
ok
No
Replace Power board.
ok

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2. Digital TV Video
Check RF Cable & Signal
Check Tuner 3.3V Power
L3703 Replace L3703
Check Tuner 1.2V Power
IC3703 2 pin : 1.2V
Check IF_P/N Signal
TU3702 17/18 Pin
Replace IC3703
Check Tuner 5V Power
L3702 Check IC406,IC410
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board.
ok
ok
ok
ok
ok
No
No
No
No
No
Replace IC406,IC410
No
Bad Tuner. Replace Tuner.
Replace L3702
ok

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3. Analog TV Video
Check RF Cable & Signal
Check Tuner 3.3V Power
L3703 Replace L3703
Check Tuner 1.2V Power
IC3703 2 pin : 1.2V
Check CVBS Signal
TU3702 11 Pin
Replace IC3703 .
Check Tuner 5V Power
L3702 Check IC406,IC410
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board.
ok
ok
ok
ok
ok
No
No
No
No
No
Replace IC406,IC410
No
Bad Tuner. Replace Tuner.
Replace L3702
ok

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4. AV Video
Check input signal format.
Is it supported?
Check AV Cable for damage
for damage or open conductor
Check JK1604 , JK9901
CVBS Signal Line
R246 , R4016
ok
ok
ok
No
Replace Jack
5. Component Video
Check input signal format.
Is it supported?
Check Component Cable
for damage or open conductor.
Check JK1601 or 1603
Y/PB/PR signal Line
ok
ok
ok
No
Replace Jack
ok
Check CVBS_DET Signal Replace R9915 or R1666
No
Check Mstar LVDS Output Replace Mstar(IC100) or Main Board.
No
Check COMP_DET Signal Replace R1614, R4223 or R1615
No
Check Mstar LVDS Output Replace Mstar(IC100) or Main Board.
ok
No

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6. RGB Video
Check input signal format.
Is it supported?
Check RGB Cable conductors
for damage or open conductor
Check EDID & EEPROM
IC1105 I2C Signal
R1141, R1143(SDA,SCL)
Check JK1104
H/V_Sync/R/G/B Signal Line
ok
ok
ok
No
No
Replace the defective IC or re-download EDID data
ok
Replace Jack
Check DSUB_DET Replace R1146 or R1147
No
Check Mstar LVDS Output Replace Mstar(IC100) or Main Board.
ok
No

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7. HDMI Video
Check input signal format.
Is it supported?
Check HDMI Cable conductors
for damage or open conductor.
Check EDID & EEPROM
IC801,IC802,IC804
I2C Signal
Check JK801, JK802, JK803
ok
ok
ok
No
No
Replace the defective IC or re-download EDID data
Check HDCP Key NVRAM(IC103)
Power & I2C Signal Replace the defective IC.
ok
No
Replace Jack
Check HDMI Signal Check other set
If no problem, check signal line
ok
No
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board.
ok
No
Replace Main Board
No
Check HDMI_DET(HPD)
No
ok
Replace R830,R828,R862