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LED TV
SERVICE MANUAL
CHASSIS : LB35A

MODEL : 22LN4050 22LN4050-TB


CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.




P/NO : MFL67732805 (1304-REV00) Printed in Korea
CONTENTS



CONTENTS .............................................................................................. 2

SAFETY PRECAUTIONS ........................................................................ 3

SERVICING PRECAUTIONS.................................................................... 4

SPECIFICATION ....................................................................................... 6

ADJUSTMENT INSTRUCTION ................................................................ 9

TROUBLE SHOOTING GUIDE............................................................... 13

BLOCK DIAGRAM.................................................................................. 23

EXPLODED VIEW .................................................................................. 24

SCHEMATIC CIRCUIT DIAGRAM ..............................................................




Copyright © LG Electronics. Inc. All rights reserved. -2- LGE Internal Use Only
Only for training and service purposes
SAFETY PRECAUTIONS

IMPORTANT SAFETY NOTICE
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 Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
An isolation Transformer should always be used during the
servicing of a receiver whose chassis is not isolated from the AC Do not use a line Isolation Transformer during this check.
power line. Use a transformer of adequate power rating as this Connect 1.5 K / 10 watt resistor in parallel with a 0.15 uF capacitor
protects the technician from accidents resulting in personal injury between a known good earth ground (Water Pipe, Conduit, etc.)
from electrical shocks. and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter
It will also protect the receiver and it's components from being with 1000 ohms/volt or more sensitivity.
damaged by accidental shorts of the circuitry that may be Reverse plug the AC cord into the AC outlet and repeat AC voltage
inadvertently introduced during the service operation. measurements for each exposed metallic part. Any voltage
measured must not exceed 0.75 volt RMS which is corresponds to
If any fuse (or Fusible Resistor) in this TV receiver is blown, 0.5 mA.
replace it with the specified. In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
When replacing a high wattage resistor (Oxide Metal Film Resistor, repaired before it is returned to the customer.
over 1 W), keep the resistor 10 mm away from PCB.
Leakage Current Hot Check circuit
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 1 M and 5.2 M.
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.




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


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



Copyright © LG Electronics. Inc. All rights reserved. -5- LGE Internal Use Only
Only for training and service purposes
SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement.


1. Application range 3. Test method
This specification is applied to the LB35A chassis. 1) Performance: LGE TV test method followed
2) Demanded other specification
- Safety : CE, IEC specification
2. Requirement for Test - EMC : CE, IEC
Each part is tested as below without special appointment.

(1) Temperature: 25 °C ± 5 °C(77 °F ± 9 °F), CST: 40 °C ± 5 °C
(2) Relative Humidity: 65 % ± 10 %
(3) Power Voltage
: Standard input voltage (AC 100-240 V~, 50/60 Hz)
* Standard Voltage of each products 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.




4. Model General Specification
* HDMI 1.4 with Deep Color is only apply for FHD Model
No. Item Specification Remarks
1. Market NON EU
PAL/SECAM B/G/D/K
2. Broadcasting system PAL-I
NTSC-M
BAND PAL(BG,I) NTSC(M) China(DK)
3. Channel Storage VHF/UHF 01-C69 2~78 C1~C69
Cable S1~S47 1~71 S1~S47
4. Receiving system Upper Heterodyne
5. Video Input PAL, SECAM, NTSC Rear (2EA)
6. Component Input Y/Cb/Cr, Y/Pb/Pr Rear (1EA)
7. USB Input MP3, JPEG,Movie Side(1EA)
8. AV Audio Output RF/AV/HDMI Audio Output Rear (1EA)
9. D-SUB INPUT S/W Upgrade Only Rear (1EA)
10. HDMI Input HDMI-DTV, Only PCM MODE Rear (2EA)
11. Audio Input (1EA) AV&Component L/R Input(2EA)




Copyright © LG Electronics. Inc. All rights reserved. -6- LGE Internal Use Only
Only for training and service purposes
5. Component Video Input (Y, PB, PR)
No. Resolution H-freq(kHz) V-freq(Hz) Pixel clock(MHz) Proposed
1. 720*480 15.73 59.94 13.500 SDTV, DVD 480I(525I)
2. 720*480 15.75 60.00 13.514 SDTV, DVD 480I(525I)
3. 720*576 15.625 50.00 13.500 SDTV, DVD 576I(625I) 50Hz
4. 720*480 31.47 59.94 27.000 SDTV 480P
5. 720*480 31.50 60.00 27.027 SDTV 480P
6. 720*576 31.25 50.00 27.000 SDTV 576P 50Hz
7. 1280*720 44.96 59.94 74.176 HDTV 720P
8. 1280*720 45.00 60.00 74.250 HDTV 720P
9. 1280*720 37.50 50.00 74.25 HDTV 720P 50Hz
10. 1920*1080 28.125 50.00 74.250 HDTV 1080I 50Hz,
11. 1920*1080 33.72 59.94 74.176 HDTV 1080I
12. 1920*1080 33.75 60.00 74.25 HDTV 1080I
13. 1920*1080 56.25 50 148.5 HDTV 1080P
14. 1920*1080 67.432 59.94 148.350 HDTV 1080P
15. 1920*1080 67.5 60.00 148.5 HDTV 1080P




6. HDMI Input
6.1. PC Mode
* Spec. out but it can be shown the picture at only HDMI/DVI IN 1 via DVI to HDMI Cable

No. Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed Remarks
1. 640×480 31.469 59.94 25.17 VESA(VGA)
2. 800×600 37.879 60.317 40.00 VESA(SVGA)
3. 1024×768 48.363 60.004 65.00 VESA(XGA)
4. 1280×768 47.776 59.87 79.5 VESA(WXGA)
5. 1360×768 47.72 59.799 84.62 VESA(WXGA)
6 1366×768 47.7 60.00 84.62 WXGA
7. 1280×1024 63.595 60.00 108.875 SXGA
8. 1920×1080 66.647 59.988 138.625 WUXGA
* Monitor Range Limits
Min Vertical Freq - 58 Hz / Max Vertical Freq - 63 Hz
Min Horiz. Freq - 28 kHz / Max Horiz. Freq - 68 kHz
Pixel Clock - 150 MHz




Copyright © LG Electronics. Inc. All rights reserved. -7- LGE Internal Use Only
Only for training and service purposes
6.2. DTV Mode
No. Resolution H-freq(kHz) V-freq.(kHz) Pixel clock(MHz) Proposed Remarks
1. 720*480 15.73 59.94 13.500 SDTV, DVD 480I(525I)
2. 720*480 15.75 60.00 13.514 SDTV, DVD 480I(525I) Spec. out but display.
3. 720*576 15.625 50.00 13.500 SDTV, DVD 576I(625I) 50Hz
4. 720*480 31.47 59.94 27 SDTV 480P
5. 720*480 31.5 60.00 27.027 SDTV 480P
6. 720*576 31.25 50.00 27 SDTV 576P
7. 1280*720 44.96 59.94 74.176 HDTV 720P
8. 1280*720 45 60.00 74.25 HDTV 720P
9. 1280*720 37.5 50.00 74.25 HDTV 720P
10. 1920*1080 28.125 50.00 74.25 HDTV 1080I
11 1920*1080 33.72 59.94 74.176 HDTV 1080I
12 1920*1080 33.75 60.00 74.25 HDTV 1080I
13 1920*1080 56.25 50.00 148.5 HDTV 1080P
14 1920*1080 67.432 59.94 148.350 HDTV 1080P
15 1920*1080 67.5 60.00 148.5 HDTV 1080P
16 1920*1080 27 24.00 74.25 HDTV 1080P
17 1920*1080 33.75 30.00 74.25 HDTV 1080P
18 1920*1080 26.97 23.97 74.25 HDTV 1080P
19 1920*1080 33.716 29.976 74.25 HDTV 1080P




Copyright © LG Electronics. Inc. All rights reserved. -8- LGE Internal Use Only
Only for training and service purposes
ADJUSTMENT INSTRUCTION
1. Application Range 3.2. EDID Download
This specification sheet is applied to all of the LED TV with HD MODEL
LB35A chassis. ** HDMI 1 : 256Bytes
0 1 2 3 4 5 6 7 8 9 A B C D E F
0 00 FF FF FF FF FF FF 00 1E 6D 01 00 01 01 01 01
10 01 17 01 03 80 A0 5A 78 0A F3 30 A4 54 46 96 26
2. Designation 20 0F 49 4B 21 08 00 45 40 01 01 61 40 01 01 01 01
(1) Because this is not a hot chassis, it is not necessary to 30 01 01 01 01 01 01 01 1D 00 72 51 D0 1E 20 6E 28
use an isolation transformer. However, the use of isolation 40 55 00 C4 8E 21 00 00 1E 1B 21 50 A0 51 00 1E 30
50 48 88 35 00 BC 77 21 00 00 1C 00 00 00 FC 00 4C
transformer will help protect test instrument.
60 47 20 54 56 0A 20 20 20 20 20 20 20 00 00 00 FD
(2) Adjustment must be done in the correct order.
70 00 3A 3F 1C 44 0F 00 0A 20 20 20 20 20 20 01
(3) The adjustment must be performed in the circumstance of 80 02 03 28 F1 4F 84 07 01 16 02 03 11 12 13 14 05
25 °C ± 5 °C of temperature and 65 % ± 10 % of relative 90 20 22 1F 10 26 11 07 50 09 7F 07 83 01 00 00 68
humidity if there is no specific designation. A0 03 0C 00 10 00 80 1E 00 01 1D 00 80 51 D0 1C 20
(4) The input voltage of the receiver must keep 100-220 V, B0 40 80 35 00 BC 88 21 00 00 1E 8C 0A D0 8A 20 E0
50/60Hz. C0 2D 10 10 3E 96 00 13 8E 21 00 00 18 8C 0A A0 14
(5) The receiver must be operated for over 5 minutes prior to D0 51 F0 16 00 26 7C 43 00 C4 8E 21 00 00 98 01 1D
the adjustment when module is in the circumstance of E0 80 18 71 1C 16 20 58 2C 25 00 C4 8E 21 00 00 9E
above 15 °C. F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

In case of keeping module is in the circumstance of 0
°C, it should be placed in the circumstance of above 15 8BIT FHD MODEL
°C for 2 hours. ** HDMI 1 : 256Bytes
In case of keeping module is in the circumstance of 0 1 2 3 4 5 6 7 8 9 A B C D E F
below -20 °C, it should be placed in the circumstance of 0 00 FF FF FF FF FF FF 00 1E 6D 01 00 01 01 01 01
above 15 °C for 3 hours. 10 01 17 01 03 80 A0 5A 78 0A D9 B0 A3 57 49 9C 25
20 11 49 4B 21 08 00 01 01 45 40 61 40 01 01 81 80
* Caution 30 01 01 D1 C0 01 01 02 3A 80 18 71 38 2D 40 58 2C
40 45 00 08 44 21 00 00 1E 1B 21 50 A0 51 00 1E 30
When a still image is displayed for 20 minutes or longer
50 48 88 35 00 BC 88 21 00 00 1C 00 00 00 FC 00 4C
(especially where W/B scale is strong. Digital pattern 13ch
60 47 20 54 56 0A 20 20 20 20 20 20 20 00 00 00 FD
and/or Cross hatch pattern 09ch), there can some 70 00 3A 3F 1C 44 0F 00 0A 20 20 20 20 20 20 01
afterimage in the black level area. 80 02 03 28 F1 4F 90 07 01 16 02 03 11 12 13 04 14
90 05 20 22 1F 26 11 07 50 09 7F 07 83 01 00 00 68
A0 03 0C 00 10 00 80 1E 00 01 1D 00 80 51 D0 1C 20

3. MAIN PCBA Adjustments B0 40 80 35 00
C0 2D 10 10 3E
BC
96
88
00
21
13
00
8E
00
21
1E
00
8C
00
0A
18
D0
8C
8A
0A
20
A0
E0
14
3.1. ADC Calibration D0 51 F0 16 00 26 7C 43 00 C4 8E 21 00 00 98 01 1D
E0 80 18 71 1C 16 20 58 2C 25 00 C4 8E 21 00 00 9E
3.1.1. Using D/L Jig F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
- An ADC calibration is automatically adjusted from DFT-Jig
- If it needs to adjust manually, refer to appendix.
a. White Balance Adjustment
* ADC Calibration Protocol (RS232) HD FHD (8Bit)
NO Item CMD 1 CMD 2 Data 0 EDID C/S data
HDMI HDMI
Enter Adjust Adjust When transfer the `Mode In',
A A 0 0 Block 0 A5 C1
MODE `Mode In' Carry the command.
Check sum
ADC Automatically adjustment 44(HDMI1) 44 (HDMI1)
ADC adjust
Adjust
A D 1 0
(The use of a internal pattern) (Hex) Block 1
34(HDMI2) 34 (HDMI2)
Adjust Sequence
aa 00 00 [Enter Adjust Mode]
xb 00 40 [Component1 Input (480i)]
ad 00 10 [Adjust 480i Comp1]
aa 00 90 End Adjust mode




Copyright © LG Electronics. Inc. All rights reserved. -9- LGE Internal Use Only
Only for training and service purposes
4. White Balance Adjustment (2) Adjustment Map
Command Data Range Default
4.1. Overview Adj. item
(lower caseASCII) (Hex.) (Decimal)
4.1.1. W/B adj. Objective & How-it-works CMD1 CMD2 MIN MAX
(1) Objective: To reduce each Panel's W/B deviation R Gain j g 00 C0
(2) How-it-works: When R/G/B gain in the OSD is at 192, it G Gain j h 00 C0
means the panel is at its Full Dynamic Range. In order to B Gain j i 00 C0
Cool
prevent saturation of Full Dynamic range and data, one of R Cut
R/G/B is fixed at 192, and the other two is lowered to find G Cut
the desired value. B Cut
R Gain j a 00 C0
(3) Adj. condition: normal temperature
G Gain j b 00 C0
1) Surrounding Temperature: 25 °C ± 5 °C
B Gain j c 00 C0
2) Warm-up time: About 5 Min Medium
R Cut
3) Surrounding Humidity: 20% ~ 80% G Cut
4) Before White balance adjustment, Keep power on B Cut
status, don't power off R Gain j d 00 C0
G Gain j e 00 C0
4.1.2. Adj. condition and cautionary items Warm B Gain j f 00 C0
(1) Lighting condition in surrounding area surrounding lighting R Cut
should be lower 10 lux. G Cut
Try to isolate adj. area into dark surrounding.
(2) Probe location: Color Analyzer(CA-210) probe should be
within 10 cm and perpendicular of the module surface 4.5. Adjustment method
(80°~ 100°)
4.5.1. Auto WB calibration
(3) Aging time
(1) Set TV in ADJ mode using P-Only key(or POWER ON key).
1) After Aging Start, Keep the Power ON status during 5
(2) Place optical probe on the center of the display.
Minutes.
- It need to check probe condition of zero calibration before
2) In case of LCD, Back-light on should be checked using
adjustment.
no signal or Full-white pattern.
(3) Connect RS-232C Cable
(4) Select mode in ADJ Program and begin a adjustment.
4.2. Equipment (5) When WB adjustment is completed with OK message,
(1) Color Analyzer: CA-210 (NCG: CH 9 / WCG: CH12 / LED: check adjustment status of pre-set mode. (Cool, Medium,
CH14) Warm)
(2) Adj. Computer (During auto adj., RS-232C protocol is (6) Remove probe and RS-232C cable.
needed) W/B Adj. must begin as start command "wb 00 00" , and
(3) Adjust Remocon finish as end command "wb 00 ff", and Adj. offset if need.
(4) Video Signal Generator MSPG-925F 720p/204-Gray
(Model: 217, Pattern: 49) 4.5.2. LED White balance table
* Color Analyzer Matrix should be calibrated using CS-1000. - If Model is Polaris Model, G-gain fix is applied.
(1) Cool Mode
4.3. Equipment connection 1) Purpose : Adjust the color temperature to reduce the
deviation of the module color temperature.
Co lo r Analyzer 2) Principle : To adjust the white balance without the
Probe RS -232C saturation, Fix the G gain to 172 (default data) and
Co m p ut er change the others (R/B Gain ).
RS -232C
RS -232C 3) Adjustment mode : mode - Cool
Pat t ern Generat o r
Signal Source (2) Medium / Warm Mode
* If TV internal pattern is used, not needed 1) Purpose : Adjust the color temperature to reduce the
deviation of the module color temperature.
2) Principle : To adjust the white balance without the
saturation, Fix the one of R/G/B gain to 192 (default
4.4. Adjustment Command (Protocol) data) and decrease the others.
(1) RS-232C Command used during auto-adj. 3) Adjustment mode : Two modes - Medium / Warm
RS-232C COMMAND
Explantion
CMD DATA ID
wb 00 00 Begin White Balance adjustment
End White Balance adjustment
wb 00 ff
(internal pattern disappears )




Copyright © LG Electronics. Inc. All rights reserved. - 10 - LGE Internal Use Only
Only for training and service purposes
4.6. Reference(White Balance Adjustment 8. GND and HI-POT Test
coordinate and color temperature) 8.1. GND & HI-POT auto-check preparation
(1) Luminance: 204 Gray, 80IRE (1) Check the POWER CABLE and SIGNAL CABE insertion
(2) Standard color coordinate and temperature using CS-1000 condition
(over 26 inch)
The spec of color temperature and coordinate.
Mode Color Temp Color coordinate Remark
8.2. GND & HI-POT auto-check
(1) Pallet moves in the station. (POWER CORD / AV CORD is
Cool x = 0.269 (±0.002) * Test signal tightly inserted)
13,000 K
(C50) y = 0.273 (±0.002) - Inner pattern for (2) Connect the AV JACK Tester.
Medium x = 0.285 (±0.002) W/B adjust (3) Controller (GWS103-4) on.
9,300 K
(0) y = 0.293 (±0.002) - External white (4) GND Test (Auto)
Warm x = 0.313 (±0.002) pattern - If Test is failed, Buzzer operates.
6,500 K (85IRE, 204gray) - If Test is passed, execute next process (Hi-pot test).
(W50) y = 0.329 (±0.002)
(Remove A/V CORD from A/V JACK BOX)
(5) HI-POT test (Auto)
* Note : x,y coordinates are drifted about 0.007 after 30 mins
- If Test is failed, Buzzer operates.
heat-run. So checking color coordinate within 5-min at
- If Test is passed, GOOD Lamp on and move to next
total assembly line, consider x,y coordinates might be
process automatically.
up to 0.007 than x,y target of each color temperature.

8.3. Checkpoint
(1) Test voltage
5. Tool Option setting & Inspection per - GND: 1.5 KV / min at 100 mA
countries - SIGNAL: 3 KV / min at 100 mA
(2) TEST time: 1 second
(1) Press 'IN START' key at Factory Service remote control.
(2) Select 'Tool Option 1'. (3) TEST POINT
(3) Punch in the number and press 'OK'. (Each of models has - GND Test = POWER CORD GND and SIGNAL CABLE
their number) GND.
(4) Correct 'Tool Option2' ~ 'Tool Option5'. - Hi-pot Test = POWER CORD GND and LIVE &
(5) Completed adjusting Tool option. NEUTRAL.
(4) LEAKAGE CURRENT: At 0.5 mArms


6. Ship-out mode check (In-stop)
After final inspection, press In-Stop key of the Adjustemnt
Remote Control and check that the unit goes to Stand-by mode.



7. AUDIO output check
7.1. Audio input condition
(1) RF input: Mono, 1KHz sine wave signal, 100% Modulation
(2) CVBS, Component: 1KHz sine wave signal (0.4Vrms)
(3) RGB PC: 1KHz sine wave signal (0.7Vrms)

7.2. Specification
Item Min Typ Max Unit Remark
Audio practical
(1) Measurement condition
max Output, L/R W
4.5 5.0 6.0 - EQ/AVL/Clear Voice: Off
(Distortion=10% Vrms
(2) Speaker (8 Impedance)
max Output)




Copyright © LG Electronics. Inc. All rights reserved. - 11 - LGE Internal Use Only
Only for training and service purposes
9. USB S/W Download 10. Optional adjustments
* optional, Service only 10.1. Manual ADC Calibration
Enter `EZ ADJUST' mode by pressing `ADJ' key.
(1) Put the USB Stick to the USB socket. Enter Internal ADC calibration mode by pressing `' or `OK'
(2) Automatically detecting update file in USB Stick. key at `7. ADC Calibration'
- If your downloaded program version in USB Stick is lower EZ ADJUST ADC Calibration
than that of TV set, it didn't work. 0. Tool Option1
ADC Comp 480i NG
Otherwise USB data is automatically detected. 1. Tool Option2
2. Tool Option3
ADC Comp 1080p NG

(3) Show the message "Copying files from memory". 3. Tool Option4
ADC RGB NG

4. Tool Option5
Start Reset
5. Tool Option Commercial
6. Country Group
7. Area Option
8. ADC Calibration
9. White Balance
10. 10 Point WB
11. Test Pattern
12. EDID D/L
13. Sub B/C
14. Ext. Input Adjust



Caution : Using `P-ONLY' key of the Factory Service
remote control when turns TV on.

10.2. Manual White balance Adjustment
10.2.1. Adjustment condition and cautionary items
(4) Updating is starting. (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
1) After Aging Start, Keep the Power ON status during 5
Minutes.
2) In case of LCD, Back-light on should be checked using
no signal or Full-white pattern.
(5) Updating Completed, The TV will restart automatically.
(6) If your TV is turned on, check your updated version and 10.2.2. Equipment
Tool option. (explain the Tool option, next stage) (1) Color Analyzer: CA-210 (NCG: CH 9 / WCG: CH12 / LED:
* If downloading version is more high than your TV have, CH14)
TV can lost all channel data. In this case, you have to (2) Adj. Computer(During auto adj., RS-232C protocol is needed)
channel recover. if all channel data is cleared, you didn't (3) Adjust Remot control
have a DTV/ATV test on production line. (4) Video Signal Generator MSPG-925F 720p/216-Gray
(Model: 217, Pattern: 78)
* After downloading, have to adjust TOOL OPTION again.
1) Push "IN-START" key in service remote control. 10.2.3. Adjustment
2) Select "Tool Option 1" and push "OK" key. (1) Set TV in Adj. mode using POWER ON.
3) Punch in the number. (Each model has their number.) (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 (Key). When
Key() is pressed 216 Gray 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 216 Gray pattern.




Copyright © LG Electronics. Inc. All rights reserved. - 12 - LGE Internal Use Only
Only for training and service purposes
TROUBLE SHOOTING
1. NO POWER-Main PCBA

NO POWER


1 Is Adapter NO check open or short at Line.
Output VOLTAGE 19.4V
or change Adapter.
through of JK700?


YES

2 check the Lines of IC701,
NO
Is 3.3V at C708? If there is any problem at Line,
Change IC701

YES

3
NO check the Lines of IC711,IC704
Is 1.8V at C745? If there is any problem at Line,
is 1.25V at C742? Change IC704,IC706.


YES
4
Check Line short or open between
NO
Check waveform of X501 IC501 and X501,
Change IC501 or change X501

YES
5
is 3.3V at 1pin of P120?
NO Change control
when push power key,
Or check Line short or open of P120
Is 0v at 2pin of P120?

YES
6
is there any waver at 11pin of P120, NO change IR board
when use remote controller? Or check Line short or open of P120




Insert F/W 4




X501


Copyright © LG Electronics. Inc. All rights reserved. - 13 - LGE Internal Use Only
Only for training and service purposes
2. No raster (Power LED blue, black screen)


NO RASTER
(Screen is not displayed)



1 NO check open or short at Line.
Is 19.4V at JK700? or change Adapter


YES
Check Line short or open between
2 Is 1.8V at L501? NO IC711/IC704 and IC501,
Is 1.25V at L500? If there is any problem at Line,
Change IC711/IC704 or change IC501
YES