LG 55LF5950 User manual

Printed in KoreaP/NO : MFL69198603 (1505-REV00)
CHASSIS : LA50H
MODEL : 55LF5950 55LF5950-UB
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
LED TV
SERVICE MANUAL
North/Latin America http://aic.lgservice.com
Europe/Africa http://eic.lgservice.com
Asia/Oceania http://biz.lgservice.com
Internal Use Only

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LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
CONTENTS
CONTENTS .............................................................................................. 2
SAFETY PRECAUTIONS ........................................................................ 3
SERVICING PRECAUTIONS.................................................................... 4
SPECIFICATION ........................................................................................6
ADJUSTMENT INSTRUCTION ................................................................ 8
BLOCK DIAGRAM.................................................................................. 16
EXPLODED VIEW .................................................................................. 20
SCHEMATIC CIRCUIT DIAGRAM ........................................... APPENDIX
TROUBLE SHOOTING GUIDE................................................. APPENDIX

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LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
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 1 W), keep the resistor 10 mm 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 1 MΩand 5.2 MΩ.
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 1.5 K / 10 watt resistor in parallel with a 0.15 uF 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
0.5 mA.
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
IMPORTANT SAFETY NOTICE
SAFETY PRECAUTIONS

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LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
SERVICING PRECAUTIONS
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 conict 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 mod-
ule 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 explo-
sion 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 specied 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 ammable mixture.
Unless specied 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 xtures specied in this
service manual.
CAUTION: Do not connect the test xture ground strap to any
heat sink in this receiver.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid-state) devices can be damaged eas-
ily by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES
devices are integrated circuits and some eld-effect transistors
and semiconductor “chip” components. The following techniques
should be used to help reduce the incidence of component dam-
age 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. Alter-
natively, obtain and wear a commercially available discharging
wrist strap device, which should be removed to prevent poten-
tial 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 expo-
sure 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 classied as “anti-static” can generate
electrical charges sufcient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufcient 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 electri-
cally 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 replace-
ment ES devices. (Otherwise harmless motion such as the
brushing together of your clothes fabric or the lifting of your
foot from a carpeted oor can generate static electricity suf-
cient 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 1.25 cm) 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 ows onto and around both the compo-
nent 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.

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LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong) through
which the IC leads are inserted and then bent at against the cir-
cuit 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 pos-
sible 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 connec-
tions).
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 con-
nected 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.

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LGE Internal Use Only
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Only for training and service purposes
SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement
.
1. Application range
This specification is applied to the LED TV used LA50H
chassis.
2. Test condition
Each part is tested as below without special appointment.
(1) Temperature: 25 °C ± 5 °C, CST: 40 °C ± 2 °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.
3. Test method
(1) Performance: LGE TV test method followed
(2) Demanded other specification
- Safety : UL, CSA, IEC specification
- EMC: FCC, ICES, IEC specification
- Wireless : WirelessHD Specification (Option)
4. General Specification
No Item Specication Remark
1 Market North America
2 Receiving System ATSC / NTSC-M / 64 QAM / 256 QAM
3 Input Voltage AC 100 ~ 240V 50/60Hz AC 120V, 50/60Hz on the label (USA)
4 Available Channel 1) VHF : 02~13
2) UHF : 14~69
3) DTV : 02-69
4) CATV : 01~135
5) CADTV : 01~135
5 Aspect Ratio 16:9
6 Tuning System FS
7 LCD Module TBD LGD 32LF5900-UA
NC430EUN-AACR1 LGD 43LF5900-UA
NC490EUN-AACR1 LGD 49LF5900-UA
LC550DUE-MGA3 LGD 55LF5950-UB
8 Operating Environment 1) Temp : 0 ~ 40 deg
2) Humidity : ~ 80 %
9 Storage Environment 1) Temp : -20 ~ 60 deg
2) Humidity : ~ 85 %

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LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
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5. Supported video resolutions
5.1. Component 2D input(Y, CB/PB, CR/PR)
No Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) 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 67.50 60 148.50 HDTV 1080P
10. 1920*1080 67.432 59.94 148.352 HDTV 1080P
5.2. HDMI Input (PC/DTV)
No. Resolution H-freq(kHz) V-freq.(kHz) Pixel clock(MHz) 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 1152*864 54.348 60.053 80.002 VESA O
7 1360*768 47.712 60.015 85.50 VESA (WXGA) X
8 1280*1024 63.981 60.020 108.00 VESA (SXGA) O
9 1920*1080 67.5 60 148.5 HDTV 1080P O
DTV
1 640*480 31.469 59.94 25.175 SDTV 480P
2 640*480 31.5 60 25.200 SDTV 480P
3 720*480 31.50 60 27.027 SDTV 480P
4 720*480 31.469 59.94 27.00 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 67.43 59.94 148.352 HDTV 1080P
11 1920*1080 27.000 24.000 74.25 HDTV 1080P
12 1920*1080 26.97 23.97 74.176 HDTV 1080P
13 1920*1080 33.75 30.000 74.25 HDTV 1080P
14 1920*1080 33.716 29.976 74.176 HDTV 1080P

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LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
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ADJUSTMENT INSTRUCTION
1. Application
This spec. sheet applies to LA50H Chassis applied LED TV all
models manufactured in TV factory
2. Specification
(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) Adjustment must be done in the correct order.
(3) The adjustment must be performed in the circumstance of
25 ±5
ºC
of temperature and 65±10% of relative humidity if
there is no specific designation
(4) The input voltage of the receiver must keep 100~240V,
50/60Hz
(5) At first Worker must turn on the SET by using Power Only
key.
(6) The receiver must be operated for about 5 minutes prior to
the adjustment when module is in the circumstance of over
15
ºC
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 still image is displayed for a period of 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
3.2. Main PCBA Adjustments
(1) ADC adjustment(OTP) : Component
(2) EDID downloads for HDMI
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)
(5) GND and HI-POT test
3.3. Appendix
(1) Tool option menu, USB Download (S/W Update, Option
and Service only)
(2) Manual adjustment for White balance.
(3) Shipment conditions, Channel pre-set
4. MAIN PCBA Adjustments
4.1. ADC Calibration
- An ADC calibration is not necessary because MAIN SoC
(LGExxxx) is already calibrated from IC Maker
4.2. MAC Address, ESN Key and Widevine
Key, DTCP Key, HDCP1.4, HDCP2.0
download
4.2.1. Equipment & Condition
1) Play file: keydownload.exe
4.2.2. Communication Port connection
(1) Key Write: Com 1,2,3,4 and 115200 (Baudrate)
(2) Barcode: Com 1,2,3,4 and 9600 (Baudrate)
4.2.3. Download process
(1) Select the download items.
(2) Mode check: Online Only
(3) Check the test process
- US, Canada models: DETECT -> MAC_WRITE ->
WIDEVINE_WRITE
(4) Play : START
(5) Check of result: Ready, Test, OK or NG
4.2.4. Communication Port connection
(1) Connect: PCBA Jig -> RS-232C Port == PC -> RS-232C
Port
4.2.5. Download
- All models (15Y LCD TV + MAC + Widevine + ESN Key +
HDCP1.4 and HDCP2.0)
4.2.6. Inspection
- In INSTART menu, check these keys.

- 9 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
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4.3. LAN port Inspection (Ping Test)
4.3.1. Equipment setting
1) Play the LAN Port Test PROGRAM.
2) Input IP set up for an inspection to Test Program.
- IP number: 12.12.2.2
4.3.2. LAN PORT inspection (PING TEST)
(1) Play the LAN Port Test Program.
(2) Connect each other LAN Port Jack.
(3) Play Test (F9) button and confirm OK Message.
(4) Remove LAN CABLE
4.4. EDID Download
4.4.1 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”.
4.4.2 Equipment
▪ Since embedded EDID data is used, EDID download JIG,
HDMI cable and D-sub cable are not need.
▪ Adjust remocon
4.4.3. EDID DATA
4.4.3.1. 2D_8bit_PCM(US) _ xvYCC : off
HDMI EDID 2D_8bit_PCM(US)_xvYCC : off
▪Reference
- HDMI1 ~ HDMI3
- In the data of EDID, bellows may be different by S/W or Input
mode.
ⓐProduct ID
HEX EDID Table DDC Function
0001 0100 Analog
0001 0100 Digital
ⓑSerial No: Controlled on production line.
ⓒMonth, Year: Controlled on production line:
ex) Monthly : ‘01’ -> ‘01’
Year : ‘2015’ -> ‘19’
ⓓModel Name(Hex): LGTV
Chassis MODEL NAME(HEX)
LA50H
00 00 00 FC 00 4C 47 20 54 56 0A 20 20 20 20 20 20 20
ⓔChecksum(LG TV): Changeable by total EDID data.
ⓔ1ⓔ2ⓔ3
HDMI1 E6 E0 X
HDMI2 E6 D0 X
HDMI3 E6 C0 X
ⓕ Vendor Specific(HDMI)
INPUT MODEL NAME(HEX)
HDMI1 67 03 0C 00 10 00 80 1E
HDMI2 67 03 0C 00 20 00 80 1E
HDMI3 67 03 0C 00 30 00 80 1E
Ω Ω Ω Ω Ω Ω Ω Ω Ω Ω ΩͲ Ωͳ Ωʹ Ω͵ ΩͶ Ωͷ
Ω ͷͷͷͷ ͷͷͷͷ ͷͷͷͷ Ͷ ͵ ᐓ ᐔ
Ω ᐕ Ͳ Ͳ ͲͶͶ Ͳ ʹ
Ω ͷ Ͳ
Ω Ͳ ͵ ʹ
Ω Ͷ ͳ ͳ
Ω Ͷ ͷ͵ Ͳ
ΩͶ Ͷ Ͳ ᐖ
Ω ᐖ ᐗ
Ω ͵ ͷ
Ω ᐘ Ͷ Ͳ
Ω ͵ ʹ ͲͲ Ͷ
Ω͵ ʹ ʹ
ΩͶ ͵ ͵ Ͷ Ͷ
Ω Ͷ ʹͲ ͵Ͳ Ͷ ͵ Ͷ
Ω
Ω ᐗ
(1) (3) Check ‘OK’ Signal

- 10 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
4.4.3.2. 2D_10bit_PCM(US) _ xvYCC : off
HDMI EDID 2D_10bit_PCM(US)_xvYCC : off
▪ Reference
- HDMI1 ~ HDMI3
- In the data of EDID, bellows may be different by S/W or Input
mode.
ⓐProduct ID
HEX EDID Table DDC Function
0001 0100 Analog
0001 0100 Digital
ⓑSerial No: Controlled on production line.
ⓒMonth, Year: Controlled on production line:
ex) Monthly : ‘01’ -> ‘01’
Year : ‘2015’ -> ‘19’
ⓓModel Name(Hex): LGTV
Chassis MODEL NAME(HEX)
LA50H
00 00 00 FC 00 4C 47 20 54 56 0A 20 20 20 20 20 20 20
ⓔChecksum(LG TV): Changeable by total EDID data.
ⓔ1ⓔ2ⓔ3
HDMI1 E6 99 X
HDMI2 E6 89 X
HDMI3 E6 79 X
ⓕ Vendor Specific(HDMI)
INPUT MODEL NAME(HEX)
HDMI1 67 03 0C 00 10 00 B8 2D
HDMI2 67 03 0C 00 20 00 B8 2D
HDMI3 67 03 0C 00 30 00 B8 2D
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
- Surrounding Temperature: 25±5 °C
- Warm-up time: About 5 Min
- Surrounding Humidity: 20% ~ 80%
- Before White balance adjustment, Keep power on status,
don’t power off
5.1.1.2. 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.
5.1.2. 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
5.1.3. Equipment connection
Ω Ω Ω Ω Ω Ω Ω Ω Ω Ω ΩͲ Ωͳ Ωʹ Ω͵ ΩͶ Ωͷ
Ω ͷͷͷͷ ͷͷͷͷ ͷͷͷͷ Ͷ ͵ ᐓ ᐔ
Ω ᐕ Ͳ Ͳ ͲͶͶ Ͳ ʹ
Ω
ͷ Ͳ
Ω Ͳ ͵ ʹ
Ω Ͳ Ͳ Ͷ ͳ ͳ
Ω Ͳ Ͳ Ͷ ͷ͵ Ͳ
ΩͶ Ͷ Ͳ ᐖ
Ω ᐖ ᐗ
Ω ͵ ͷ
Ω ᐘ Ͷ Ͳ
Ω ͵ ʹ ͲͲ Ͷ
Ω͵ ʹ ʹ ͲͲ
ΩͶ ͵ ͵ Ͷ Ͷ ͲͲ
Ω Ͷ ʹͲ ͵Ͳ Ͷ ͵ Ͷ Ͳ
ΩͲ Ͳ ͳ
Ω ͲͲ Ͳ ᐗ
Color Analyzer
Computer
Pattern Generator
RS-232C
RS-232C
RS-232C
Probe
Signal Source
* If TV internal pattern is used, not needed

- 11 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
5.1.4. Adjustment Command (Protocol)
(1) RS-232C Command used during auto-adj.
RS-232C COMMAND Explanation
CMD DATA ID
Wb 00 00 Begin White Balance adj.
Wb 00 ff End White Balance adj.
(internal pattern disappears )
(2) Adjustment Map
Adj.
item
Command
(lower caseASCII)
Data Range
(Hex.)
Default
(Decimal)
CMD1 CMD2 MIN MAX TBD
Cool R Gain j g 00 C0 TBD
G Gain j h 00 C0 TBD
B Gain j i 00 C0 TBD
Medium R Gain j a 00 C0 TBD
G Gain j b 00 C0 TBD
B Gain j c 00 C0 TBD
Warm R Gain j d 00 C0 TBD
G Gain j e 00 C0 TBD
B Gain j f 00 C0 TBD
5.1.5. Adjustment method
5.1.5.1. Auto WB calibration
(1) Set TV in ADJ mode using P-ONLY key (or POWER ON
key)
(2) Place optical probe on the center of the display
- It need to check probe condition of zero calibration before
adjustment.
(3) Connect RS-232C Cable
(4) Select mode in ADJ Program and begin a adjustment.
(5) When WB adjustment is completed with OK message,
check adjustment status of pre-set mode (Cool, Medium,
Warm)
(6) Remove probe and RS-232C cable.
▪ 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 adjustment
(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 à 9. White-
Balance then press the cursor to the right (KEY►). When
KEY(►) is pressed 206 Gray internal pattern will be
displayed.
(4) Adjust Cool modes
(i) Fix the one of R/G/B gain to 192 (default data) and
decrease the others.
(If G gain is adjusted over 172 and R and B gain less
than 192 , Adjust is O.K.)
(ii) If G gain is less than 172,
Increase G gain by up to 172, and then increase R gain
and G gain same amount of increasing G gain.
(iii) If R gain or B gain is over 255,
Readjust G gain less than 172, Conform to R gain is 255
or B gain is 255
(5) Adjust two modes (Medium / Warm) Fix the one of R/G/B
gain to 192 (default data) and decrease the others.
(6) Adj. is completed, Exit adjust mode using “EXIT” key on
Remote controller.
5.1.6. Reference (White Balance Adj. coordinate and
color temperature)
▪ Luminance: 204 Gray, 80IRE
▪ Standard color coordinate and temperature using CS-1000
(over 26 inch)
Mode Coordinate Temp △uv
X Y
Cool 0.271 0.270 13,000K 0.0000
Medium 0.286 0.289 9,300K 0.0000
Warm 0.313 0.329 6,500K 0.0000
▪ Standard color coordinate and temperature using
CA-210(CH-14) – by aging time
(1) Normal line (From January to February) LGD
Aging time
(Min)
Cool Medium Warm
X Y X Y X Y
271 270 286 289 313 329
1 0-2 286 295 301 314 328 354
2 3-5 284 290 299 309 326 349
3 6-9 282 287 297 306 324 346
4 10-19 279 283 294 302 321 342
5 20-35 276 278 291 297 318 337
6 36-49 274 275 289 294 316 334
7 50-79 273 272 288 291 315 331
8 80-119 272 271 287 290 314 330
9 Over 120 271 270 286 289 313 329

- 12 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
▪ Standard color coordinate and temperature using
CA-210(CH-14) – by aging time
(2) Normal line (From March to December) : LGD
Aging time
(Min)
Cool Medium Warm
X Y X Y X Y
271 270 286 289 313 329
1 0-2 282 289 297 308 324 348
2 3-5 281 287 296 306 323 346
3 6-9 279 284 294 303 321 343
4 10-19 277 280 292 299 319 339
5 20-35 275 277 290 296 317 336
6 36-49 274 274 289 293 316 333
7 50-79 273 272 288 291 315 331
8 80-119 272 271 287 290 314 330
9 Over 120 271 270 286 289 313 329
▪ O/S Module (AUO, INX, Sharp, CSOT, BOE)
cool med warm
xyxyxy
spec 271 270 286 289 313 329
target 278 280 293 299 320 339
5.2. Tool Option setting & Inspection per
countries
5.2.1. Overview
(1) Tool option selection is only done for models in Non-USA
North America due to rating
(2) Applied model: LA46H Chassis applied to CANADA and
MEXICO
5.2.2. Country Group selection
(1) Press ADJ key on the Adj. R/C, and then select Country
Group Menu
(2) Depending on destination, select US, then on the lower
Country option, select US, CA, MX.
Selection is done using +, - KEY
5.2.3. Tool Option inspection
▪ Press Adj. key on the Adj. R/C, then select Tool option
※Tool option can be reconstructed by Software
5.2.4. Area Option
Area Area Option
USA 22282
CANADA 22411
MEXICO 22540
5.3. Magic Motion remote controller Check
5.3.1. Test equipment
▪ RF-remote controller for check, IR-KEY-CODE remote
controller.
▪ Check AA battery before test. A recommendation is that a
tester change battery every lots.
5.3.2. Test
(1) Make pairing with TV set by pressing “Start key(Wheel
key)” on RCU.
(2) Check a cursor on screen by pressing ‘Wheel key” of RCU
(3) Stop paring with TV set by pressing “Back+ Home” key of
RCU
5.3.3. Applied models
Chassis Remark
LA50H Bluetooth Spec out
※Dongle Model : An USB dongle-type receiver will be
supplied in form of accessory. So this
pairing test is not necessary for these
models
5.4. Wi-Fi MAC Address Check
5.4.1. Using RS232 Command
Command Set ACK
Transmission [A][l][][Set ID][][20][Cr] [O][K][x] or [N][G]
5.4.2. Check the menu on in-start
5.5. HDMI ARC Function Inspection
5.5.1. Test equipment
- Optic Receiver Speaker
- MSHG-600 (SW: 1220 ↑)
- HDMI Cable (for 1.4 version)
5.5.2. Test method
(1) Insert the HDMI Cable to the HDMI ARC port from the
master equipment (HDMI1)
(2) Check the sound from the TV Set
(3) Check the Sound from the Speaker or using AV & Optic
TEST program (It’s connected to MSHG-600)

- 13 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
5.5. HDMI ARC Function Inspection
5.5.1. Test equipment
- Optic Receiver Speaker
- MSHG-600 (SW: 1220 ↑)
- HDMI Cable (for 1.4 version)
5.5.2. Test method
(1) Insert the HDMI Cable to the HDMI ARC port from the
master equipment (HDMI1)
(2) Check the sound from the TV Set
(3) Check the Sound from the Speaker or using AV & Optic
TEST program (It’s connected to MSHG-600)
* Remark: Inspect in Power Only Mode and check SW version
in a master equipment
5.6. EYE-Q Green Function Inspection
Step 1) Turn on the TV..
Step 2) Press 'EYE button' on the adjustment remote-
controller.
Step 3) Cover 'Eye Q sensor' on the front of set with your
hands, hold it for 6 seconds.
Step 4) Check "the Sensor Data" on the screen, make certain
that Data is below 10. If Data isn’t below 10 in 6
seconds, Eye Q sensor would be bad. You should
change Eye Q sensor.
Step 5) Uncover your hands from Eye Q sensor, hold it for 6
seconds.
Step 6) Check "Back Light(xxx)" on the screen, check data
increase . You should change Eye Q sensor
5.7. Ship-out mode check (In-stop)
▪ After final inspection, press In-Stop key of the Adj. R/C and
check that the unit goes to Stand-by mode
6. AUDIO output check
6.1. Audio input condition
(1) RF input: Mono, 1KHz sine wave signal, 100% Modulation
(2) CVBS, Component: 1KHz sine wave signal (0.4Vrms)
6.2. Specification
No Item Min Typ Max Unit Remark
1 Audio practical
max Output,
L/R
(Distortion=10%
max Output)
4.5
5.2
5
5.477
6
6
W
Vrms
(1) Measurement
condition
- EQ/AVL/Clear
Voice: Off
(2) Speaker (8Ω
Impedance)

- 14 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
7. GND and HI-POT Test
7.1. GND & HI-POT auto-check preparation
(1) Check the POWER CABLE and SIGNAL CABE insertion
condition
7.2. 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.
<Tuner GND is separated>
7.3. Checkpoint
(1) Test voltage
(2) TEST time: 1 second
(3) TEST POINT
- GND Test = POWER CORD GND and SIGNAL CABLE GND.
- Hi-pot Test = POWER CORD GND and LIVE & NEUTRAL.
(4) LEAKAGE CURRENT: At 0.5mArms
8. USB S/W Download
(optional, 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 lower
than that of TV set, it didn’t work. Otherwise USB data is
automatically detected.
(3) Show the message “Copying files from memory”
(4) Updating is staring.
(5) Updating Completed, The TV will restart automatically
(6) If your TV is turned on, check your updated version and
Tool option.
* 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, TOOL OPTION setting is needed 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.)

- 15 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
9. Optional adjustments
9.1. Manual White balance Adjustment
9.1.1. 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
i) After Aging Start, Keep the Power ON status during 5
Minutes.
ii) In case of LCD, Back-light on should be checked using no
signal or Full-white pattern.
9.1.2. 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/216-Gray
(Model: 217, Pattern: 78)
9.1.3. Adjustment
(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 (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.

- 16 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
BLOCK DIAGRAM
IC101
A5LR
I2C_1Audio AMP
Digital Demod
IF (+/-)
Analog Demod
Tuner : I2C_2
Sub Micom
(R5F100GEAFB)
I2C 3
IR / KEY
IR
KEY
I2C
HDMI
MUX
LVDS
USB
SPDIF OUT
ETHERNET
USB1
USB2
OCP
1.5A
OCP
1.5A
S
I
D
E
HDMI1
HDMI2
(ARC)
SIDE
R
E
A
R
OPTIC
LAN
SYSTEM EEPROM
(256Kb)
51P
eMMC 5.0
(4GB)
DDR3 1600 X 16
(512MB X 1EA, 256MBx1EA)
I2C 1
X_TAL
24MHz
WIFI
SUB
ASSY
USB_WIFI
I
F
(
+
+
+
+
+
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
-
)
jpG
P_TS P_TS
Rear
Tuner
S
P
D
I
F
O
U
T
(
A
R
C
)
O
P
T
I
C

- 17 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
33Ω
+3.3V_NORMAL
3.3KΩ
TUNER
3.3KΩ
+3.3V_NORMAL
,&B6'$
,&B6&/
,&B6'$
,&B6&/
33Ω
+3.3V_NORMAL
3.3KΩ
IC5600
NTP7515(AMP)
,&B6'$
,&B6&/
100 Ω
,&B6'$
,&B6&/ TUNER (Demod)
3.3KΩ
+3.3V_NORMAL
33Ω
IC101
A5LR
IC3000
R5F100GEAFB MICOM
IC100
NVRAM33Ω
33ΩIC6900
LNB
IR / KEY/EYE
100Ω
3.3KΩ
(<(B,&B6'$
(<(B,&B6&/
+3.5V_ST
I2C Block Diagram

- 18 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
Tuner /CI Block Diagram

- 19 -
LGE Internal Use Only
Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
13.2V
PSU
AMP
3.4V_Normal
Switch Cir
(TR+FET)
TPS56428
(4A)
WIFI
TPS65282REGR
(4A)
OCP_AP2151WG-7
(0.5A) CI Slot
USB1
USB2
BD86106EFJ
(6A) A5LR_Core
LNB Switch Cir
(TR+FET) LNB
Panel VccSwitch
Cir (TR+FET) Panel
AZ1117EH_ADJ
(1A)
TJ2132
(2A)
EmmC
TUNER
D_Demod_Core
IR/KEY
Micom
Z* -only
A5LR
Tuner
AMP
Earphone
AMP
NVRAM
OPTIC
JACK
SCART OPAMP
EmmC
Scart Out
Buffer IC
DC DC Converter
LDO
3.4V
3.4V
5V
1.2V
13V
13V
OCP_AP2191WG
(1.6A)
1.8V
1.2V
TJ2132
(2A)
DDR
1.5V
0.6A
0.3A
1A
0.5A
2.4A 0.72A1.8A
0.45A
0.63A
2.86A
0.3A
1.5A
1.5A
0.5A1.56A
Other Device
Power Block Diagram

- 20 - LGE Internal Use OnlyCopyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
EXPLODED VIEW
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.
IMPORTANT SAFETY NOTICE
900
200
400
410
540
521
530
820
120
121
LV1
A2 A10
Set + Stand
350
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