LG 24LM530S-PU User manual

P/NO :
CHASSIS :
MODEL :
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
SERVICE MANUAL
Copyright © 2020 LG Electronics Inc. All rights reserved. Only training and service purposes.
Any reproduction, duplication, distribution (including by way of email, facsimile or other electronic means),
publication, modification, copying or transmission of this Service Manual is STRICTLY PROHIBITED unless you
have obtained the prior written consent of the LG Electronics entity from which you received this Service Manual.
The material covered by this prohibition includes, without limitation, any text, graphics or logos in this Service
Manual.
P/NO : MFL70446513 (2003-REV00)
24LM530S 24LM530S-PU
LB70B
LED TV

- 2 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
CONTENTS
CONTENTS .............................................................................................. 2
SAFETY PRECAUTIONS ......................................................................... 3
SERVICING PRECAUTIONS.................................................................... 4
SPECIFICATION ....................................................................................... 6
SOFTWARE UPDATE............................................................................... 9
BLOCK DIAGRAM.................................................................................. 10
EXPLODED VIEW .................................................................................. 11
TROUBLE SHOOTING GUIDE................................................. APPENDIX

- 3 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the
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
0.15µF
To Instrument's
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
When 25A is impressed between Earth and 2nd Ground
for 1 second, Resistance must be less than 0.1
*Base on Adjustment standard
IMPORTANT SAFETY NOTICE
SAFETY PRECAUTIONS

- 4 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
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

- 5 - Copyright © LG Electronics Inc. All rights reserved.
Only 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 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.

- 6 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
SPECIFICATION
NOTE : Specications and others are subject to change without notice for improvement.
1. Application Range
This spec sheet is applied to the LB70B chassis.
2. Specication
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
(100 V - 240 V ~, 50 / 60 Hz)
· Standard Voltage of each products is marked by models
4) Specication and performance of each parts are followed
each drawing and specication by part number in accord-
ance with BOM.
5) The receiver must be operated for about 20 minutes prior to
the adjustment.
3.Test method
1) Performance : LGE TV test method followed
2) Demanded other specication
- Safety : CE,IEC specication
- EMC : CE,IEC specication
4. General Specication
No. Item Specication Remarks
1 Market AMERICA, CANADA, MEXICO
2 Broadcasting system ATSC
3 Available Channel VHF 2-13, UHF 14-69, CATV
1-135, DTV 2-69, CADTV 1-135
4 Receiving system ATSC / NTSC-M / 64 & 256 QAM
5 Video Input NTSC-M Rear 1EA (Common AV/Component)
6 Component Input Y/Cb/Cr, Y/ Pb/Pr
7 HDMI Input PC(HDMI version 1.4) / DTV
format, Support HDCP
2EA (Rear 2)
Support ARC only HDMI1
8 Audio Input Component / AV Audio Rear 1EA (Common Component / AV)
9 SPDIF out(1EA) Optical Audio out Rear 1EA
10 H/P out Head phone out
11 USB Input(2EA) EMF, MPEG, For SVC
(download)
Side 1EA
JPEG, MP3, MPEG
12 LAN LAN port Rear 1EA

- 7 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
5. External Input Support Format
5.1. Component (Y, PB, PR)
No. Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Remark
1 720*480 15.75 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 27.00 SDTV 480P
5 720*576 15.625 50* 13.5 SDTV 576I
6 720*576 31.25 50* 13.5 SDTV 576P
7 1280*720 37.5 50* 74.25 HDTV 720P
8 1280*720 45.00 60.00 74.25 HDTV 720P
9 1280*720 44.96 59.94 74.176 HDTV 720P
10 1929*1080 28.125 50* 74.25 HDTV 1080I
11 1920*1080 33.75 60.00 74.25 HDTV 1080I
12 1920*1080 33.72 59.94 74.176 HDTV 1080I
13 1920*1080 56.25 50* 148.5 HDTV 1080P
14 1920*1080 67.50 60 148.50 HDTV 1080P
15 1920*1080 67.432 59.94 148.352 HDTV 1080P
5.2. HDMI : EDID DATA : Refer to adjust specication.
5.2.1. DTV mode
No. Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Remark
1 640 x 480 31.46 59.94 SDTV 480P
2 640 x 480 31.5 60.00 SDTV 480P
3 720 x 480 15.73 59.94 SDTV 480I
Comment Only Spec. Sheet
(Spec Out)
4 720 x 480 15.75 60.00 SDTV 480I
5 720 x 576 15.62 50.00 SDTV 576I(DVB)
6 720 x 480 31.47 59.94 SDTV 480P
7 720 x 480 31.5 60.00 SDTV 480P
8 720 x 576 31.25 50.00 SDTV 576P(DVB) DVB Only
9 1280 x 720 44.96 59.94 HDTV 720P
10 1280 x 720 45 60.00 HDTV 720P
11 1280 x 720 37.5 50.00 HDTV 720P(DVB) DVB Only
12 1920 x 1080 28.12 50.00 HDTV 1080I(DVB) DVB Only
13 1920 x 1080 33.72 59.94 HDTV 1080I
14 1920 x 1080 33.75 60.00 HDTV 1080I
15 1920 x 1080 26.97 23.97 HDTV 1080P
16 1920 x 1080 27.00 24.00 HDTV 1080P
17 1920 x 1080 33.71 29.97 HDTV 1080P
18 1920 x 1080 33.75 30.00 HDTV 1080P
19 1920 x 1080 56.25 50.00 HDTV 1080P(DVB) DVB Only
20 1920 x 1080 67.43 59.94 HDTV 1080P
21 1920 x 1080 67.5 60.00 HDTV 1080P

- 8 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
5.2.2. PC mode
No. Resolution H-freq(kHz) V-freq.(Hz) Proposed Remark
1 640 x 350 @70Hz 31.46 70.09 EGA
2 720 x 400 @70Hz 31.46 70.08 DOS
3 640 x 480 @60Hz 31.46 59.94 VESA(VGA)
4 800 x 600 @60Hz 37.87 60.31 VESA(SVGA)
5 1024 x 768 @60Hz 48.36 60.00 VESA(XGA)
6 1152 x 864 @60Hz 54.34 60.05 VESA
7 1360 x 768 @60Hz 47.71 60.01 VESA(WXGA)
8 1280 x 1024 @60Hz 63.98 60.02 VESA(SXGA) FHD only
9 1920 x 1080 @60Hz 67.5 60.00 WUXGA(CEA 861D) FHD only

- 9 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
1. USB Download
1) Put the USB Stick to the USB socket
2) Automatically detecting update le in USB Stick
- If your downloaded program version in USB Stick is Lower,
it didn’t work. But your downloaded version is Higher, USB
data is automatically detecting (Download Version High &
Power only mode, Set is automatically Download)
3) Show the message “Copying les from memory”
4) Updating is starting.
5) Updating Completed, The Set will restart automatically
6) If your SET is turned on, check your updated version and
Tool option. (explain the Tool option, next stage)
* If downloading version is more high than your SET have,
SET 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 control.
2) Select "Tool Option 1" and Push “OK” button.
3) Punch in the number. (Each model has their number.)
SOFTWARE UPDATE

- 10 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
BLOCK DIAGRAM
IC101
I2C_1 Audio AMP
CVBS1
Sub Micom
I2C 3
IR / KEY
HDMI MUX
LVDS
USB
SPDIF OUT
ETHERNET
USB1 OCP
1.5A
HDMI1 HDMI2
(ARC)
REAR
R E A R
Optical Digital Audio out
LAN
SYSTEM EEPROM (256Kb)
30P
eMMC 5.0
(4GB)
DDR3 1066MHz (512MBx2EA)
I2C 1
X_TAL 24MHz
WIFI
(Built-in)
SUB ASSY
USB_WIFI
Tuner
AV/Component CVBS, Y/Pb/Pr, L/R
SIDE
TU_CVBS
TU_SCL/SDA
X_TAL 32.768KHz
IR
KEY
TU_SIF SIFP
I2C_2

Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
EXPLODED VIEW
200
540
541
570
300 400
900
800
LV1AR1
ARC1
HW1
720 730
700
831
120
HB1
HC1
HS1
or
510
832
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts
are identified by in the 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

TROUBLE SHOOTING GUIDE
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

No. Error symptom (High category) Error symptom (Mid category) Page Remarks
1
A. Video error
No video/Normal audio 1
2 No video/No audio 2
3 Tuning fail, Picture broken/ Freezing 3
4 Color error 4
5 Vertical/Horizontal bar, residual image, light spot,
external device color error 5
6 B. Power error No power 6
7 Off when on, off while viewing, power auto on/off 7
8 C. Audio error No audio/Normal video 8
9 Wrecked audio/discontinuation/noise 9
10 D. Function error Remote control & Local switch checking 10
11 External device recognition error 11
12 E. Noise Circuit noise, mechanical noise 12
13 F. Exterior error Exterior defect 13
* First of all, Check whether there is SVC Bulletin in GSCS System for these model.
Contents of Standard Repair Process
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

Y
N
Move to
No video/No audio
No video
Normal audio Check Back Light On with naked eye Check LVDS 12 V of Main B/D Replace Module
Replace Main
B/D or Repair parts
Check Main B/D to LED Back light Voltage
Replace Module
Replace Main
B/D or Repair parts
Always check & record S/W Version and White
Balance value before replacing the Main Board Replace Main Board Re-enter White Balance value
※Precaution
☞A4☞A1
☞A2
☞A3 & A6
First of all, Check whether all of cables between board is inserted properly or not.
(Main B/D ↔ Adaptor, LVDS Cable, Speaker Cable, IR B/D Cable…)
Normal
Audio On
Y
N
Normal
Voltage
Normal
Voltage
Y
N
Y
N
Error Symptom
A. Video Error
Established date
1/13
Content
No video / Normal audio
Revised date
Standard Repair Process
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

Check voltage 19V
of Adaptor
No video /
No audio Replace Main B/D or Repair parts
Replace Adaptor
Normal
Voltage
Y
N
Error Symptom
A. Video Error
Established date
2/13
Content
No video / No audio
Revised date
Standard Repair Process
☞A13
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

Y
N
☞A5
N
Check RF Signal level
Check RF Cable
Connection
1. Reconnection
2. Install Booster
Check
S/W Version
S/W Upgrade
Check whether other equipments have problem or not.
(By connecting RF Cable at other equipment)
→ DVD Player ,Set-Top-Box, Different maker TV etc`
Replace
Main B/D
Check
Tuner soldering
Y
N
Y
Y
. By using Digital signal level meter
. By using Diagnostics Setting on OSD
( Setting → Customer Support(red button on remote control) → Signal Test )
- Signal strength (Normal : over 50%)
- Signal quality (Normal : over 50%)
Y
Contact with signal distributor
or broadcaster (Cable or Air)
N
N
Y
N
☞A6
End
Normal
Signal
Normal
Picture
Normal
Picture
Normal
Picture
SVC
Bulletin
End
End
Normal
Picture
Error Symptom
A. Video Error
Established date
3/13
Content
Tuning fail, Picture broken/freezing
Revised date
Standard Repair Process
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

Color
error
Y
N
Check and
replace Link
Cable
(LVDS) and
contact
condition
Y
N
Replace Main B/D
Check error
color input
mode
Check color by input
- External Input
(COMPONENT/AV/HDMI)
Y
Check external
device and
cable Replace Main B/D
N
☞A7
N
Y
Replace module
Request repair
for external
device/cable
Check Test pattern
☞A10
☞A8 / A9
End
Color
error Color error
External
device/
Cable
Normal
External
Input
Compon
ent,
HDMI
error
Error Symptom
A. Video Error
Established date
4/13
Content
Color error
Revised date
Standard Repair Process
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

N
Y
Check external
device
connection
condition
Y
N
Check and
replace Link
Cable
Y
Replace
Module
Check color condition by input
- External Input
(Component/AV/HDMI)
Vertical/Horizontal bar, residual image, light spot
Request repair
for external
device
☞A10
External device screen error-Color error Connect other external
device and cable
(Check normal operation of
External Input, Component
and HDMI by connecting
Jig, pattern Generator,
Set-top Box etc.
N
Y
Replace
Main B/D
Check screen
condition by input
-External Input
(Component/AV/
HDMI)
Request repair for
external device
Check S/W Version Y
N
S/W Upgrade
Y
N
Y
N
Replace Main B/D
Replace
Module
☞A7 ☞A8/ A9
Check Test pattern
N
End
Screen
normal Screen normal Screen normal Screen normal
Screen
normal
End
End
Check
Version
Normal
Screen
External
Input
error
Error Symptom
A. Video Error
Established date
5/13
Content
Vertical/Horizontal bar, Residual Image,
Light spot, External device Color error
Revised date
Standard Repair Process
Y
N
End
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

Power
LED On
Y
N
DC Power on
by pressing Power Key
On Remote control
Y
N
Check Adaptor/
Power cord
was inserted properly
Check
Power LED Replace
Main B/D
N
Y
Check ST-BY 3.4V
N
Replace Adaptor or
Replace Main B/D
Y
☞A11
☞A16
Stand-By : Red
※
Power
LED On
Normal
Voltage
Normal
Operati
on
Error Symptom
B. Power Error
Established date
6/13
Content
No power
Revised date
Standard Repair Process
End
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.

Normal
Voltage
N
Y Check Power Off
Mode
Fix A/C cord & Outlet
Replace Main B/D
(If Power Off mode
is not displayed)
Check Adaptor
voltage
Y
N
Replace Main B/D
Replace Adaptor
Replace Adaptor
N
Y
☞A14
☞A13
Status Power off List Explanation
Normal
"POWEROFF_REMOTEKEY" Power off by REMOTE CONTROL
"POWEROFF_OFFTIMER" Power off by OFF TIMER
"POWEROFF_SLEEPTIMER" Power off by SLEEP TIMER
"POWEROFF_INSTOP" Power off by INSTOP KEY
"POWEROFF_AUTOOFF" Power off by AUTO OFF
"POWEROFF_ONTIMER" Power off by ON TIMER
"POWEROFF_RS232C" Power off by RS232C
"POWEROFF_RESREC" Power off by Reservated Record
"POWEROFF_RECEND" Power off by End of Recording
"POWEROFF_SWDOWN" Power off by S/W Download
"POWEROFF_UNKNOWN" Power off by unknown status except listed case
Abnormal "POWEROFF_ABNORMAL1" Power off by abnormal status except CPU trouble
"POWEROFF_CPUABNORMAL" Power off by CPU Abnormal
* Please refer to the all cases which
can be displayed on power off mode.
Adaptor
DC Out
CPU
Abnorm
al
Abnorm
al1
Normal End
Error Symptom
B. Power Error
Established date
7/13
Content
Off when on/off while viewing, power auto on/off
Revised date
Standard Repair Process
Replace
Adaptor
Y
Error N
Check outlet
or A/C cord
Copyright © 2020 LG Electronics. Inc. All rights reserved.
Only training and service purposes.