LG 27BK67U User manual

P/NO :
CHASSIS :
MODEL :
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
SERVICE MANUAL
Copyright © 2018 LG Electronics Inc. All rights reserved. Only training and service purposes.
CONFIDENTIAL
P/NO : MFL70211506 (1807-REV00)
LED MONITOR
SERVICE MANUAL
LM8BA
27BK67U

- 2 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
CONTENTS .............................................................................................. 2
SAFETY PRECAUTIONS ........................................................................ 3
SPECIFICATION ....................................................................................... 4
ADJUSTMENT INSTRUCTION ................................................................ 6
BLOCK DIAGRAM ................................................................................... 7
EXPLODED VIEW .................................................................................... 8
DISASSEMBLY ........................................................................................ 9
TROUBLE SHOOTING GUIDE .............................................................. 11
CONTENTS

- 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 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
To Instrument's
exposed
METALLIC PARTS
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
AC Volt-meter
SAFETY PRECAUTIONS

- 4 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
SPECIFICATION
No Remark
1BRAND : LGE Product
3
4
5PCB, Product spec., Adjustment spec.
External SW & Adj. Joystick switch Up / Down / Left / Right / OK Press and Hold : Power off
Function
Item Content
Customer BRAND
General
Scope
2 User Model Name 27UK670 / 27BK67U
Sale region Worldwide
Feature 27 ”LCD MONITOR (IPS UHD)
Chassis Name LM8BA
6
B2C model name : 27UK670
B2B model name : 27BK67
U
Picture Mode, Ratio, S.E.S, Six Color, On Screen
Control Dual Controller
HDMI IN
DP IN
USB-C IN
USB DN
H/P OUT
RS-232C
Length 1.55±0.05m:
Weight 0.174kg ±10%,
Color
Black
p
8 Power Cord
N/A
7 Input
HDMI1(2.0) / HDMI2 (2.0) /HDMI1(1.4) / HDMI2
*PD ; Power delivery
Do not support Quick charging
Refer to Suffix standard and power cord
Table.
-. A
pp
l
y
in
g
model : 27UK670
/
C
ontro
l
,
D
ua
l
C
ontro
ll
er,
Display Port (1.2) / Display Port (1.0)
DP(1.2),*PD 40W, USB Data
USB 3.0 Downstream x 2
Audio L/R
Color
Black
Length 0.2 ±0.01m
Weight 0.02kg ±10%,
Color Black
Length 1.5 ±0.05m
Weight 0.062kg ±10%
Color Black
1) CABLE : 90 Ω±15Ω
2) CONNECTOR : 90Ω±10Ω
Len
g
th 1.50m±0.05m
Phone to RS-232
USB C To C Cable
Impedance
.
Applying
model
:
27UK670
/
P/N : EAD63932604
(Refer to BOM)
-. Applying model : 27UK670 /
27BK67U
Do not provide
Length
1.50m
±
0.05m
Weight 0.136kg ±10%
Color Black
1) CABLE : 100Ω±5Ω
2) CONNECTOR : 100Ω±10Ω
HDMI Length 1.50m ±0.05m
(1.5m / 1.8m) Weight 0.090kg ±10%
Color Black
1) CABLE : 100Ω±5Ω
2) CONNECTOR : 100Ω±10Ω
Cable9
DisplayPort
Impedance
Impedance
P/N : EAD63749401
(Refer to BOM)
-. Applying model : 27UK670
P/N : EAD63954401
(Refer to BOM)
-. Applying model : 27UK670
Length 1.80m ±0.05m
Weight 0.10kg ±10%
Color Black
1) CABLE : 100Ω±5Ω
2) CONNECTOR : 100Ω±10Ω
11 Request to regulation team
12 Not applied
P/N : EAY63032209 (Refer to BOM)
Power Rating Input : DC 19V / 5.0A
Accessory Box -
Impedance
10 Power (Adapter / PSU
/LPB)
Output: DC 19V 5.79A, 110W Adapter
Color: Black, Weight : 0.44kg ±10%
P/N : EAD63954403
(Refer to BOM)
-. Applying model : 27BK67U
P/No S
p
ecification 27” UHD MODULE
(
LG Dis
p
la
y)
EAJ63750101 LM270WR3-SSA1 For KR Suffix : EAJ64207901
13 Applying module list

- 5 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
2. Signal Timing (Resolution)
2.1. Signal (Video & Sync) – Display Port & USB C
H(Pixels) - 31.469 800 640 16 96 48
V(Lines) - 59.94 525 480 10 2 33
H(Pixels) + 37.879 1056 800 40 128 88
V(Lines) + 60.317 628 600 1 4 23
H(Pixels) - 48.363 1344 1024 24 136 160
V(Lines) - 60 806 768 3 6 29
H(Pixels) + 54.347 1472 1152 32 96 192
V(Lines) + 60.05 905 864 1 3 37
1152 x 8644 79.99
800 x 60042 0
1024 x 76863 5
640 x 480
Resolution
1 25.175
Mode section polarity Back
Porch(B)
DOT CLOCK
[MHz]
Frequency
[kHz]/[Hz]
Total
Period(E)
Display
(A)
Front
Porch(D)
Sync.
(C)
H(Pixels) + 45 1650 1280 110 40 220
V(Lines) + 60 750 720 5 5 20
H(Pixels) - 49.702 1680 1280 72 128 200
V(Lines) + 59.81 831 800 3 6 22
H(Pixels) + 63.981 1688 1280 48 112 248
V(Lines) + 60.02 1066 1024 1 3 38
H(Pixels) + 60 1800 1600 24 80 96
V(Lines) + 60 1000 900 1 3 96
H(Pixels) + 67.5 2200 1920 88 44 148
V(Lines) - 60 1125 1080 4 5 36
H(Pi l )
133 32
2080
1920
48
32
160
1600 x 9008 108
1920 x 10809 148.5
1280 x 8006 83.5
1280 x 10247 108
1280 x 7205 74.25
H(Pixels) + 133.32 2080 1920 48 32 160
V(Lines) - 60 2222 2160 54 5 3
H(Pixels) + 88.79 2720 2560 48 32 80
V(Lines) - 59.95 1481 1440 3 5 33
H(Pixels) + 66.66 4000 3840 8 144 8
V(Lines) - 30 2222 2160 54 5 3
H(Pixels) + 133.32 4000 3840 8 144 8
V(Lines) - 60 2222 2160 54 5 3
3840 x 216012 266.64
13) Recommended Timing
3840 x 216013 533
1920 x 216010 277.25
2560 x 144011 241.5

- 6- Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
2. Signal Timing (Resolution)
2.2. Signal (Video & Sync) – HDMI
H(Pixels) -31.469 800 640 16 96 48
V(Lines) - 59.94 525 480 10 2 33
H(Pixels) + 37.879 1056 800 40 128 88
V(Lines) + 60.317 628 600 1 4 23
H(Pixels) - 48.363 1344 1024 24 136 160
V(Lines) - 60 806 768 3 6 29
H(Pixels) + 54.347 1472 1152 32 96 192
V(Lines) + 60.05 905 864 1 3 37
H(Pixels) + 45 1650 1280 110 40 220
Frequency
[kHz]/[Hz]
Total
Period(E)
Display
(A)
Front
Porch(D)
Sync.
(C)
Back
Porch(B)
4 79.99 1152 x 864
800 x 600
3 65 1024 x 768
1 25.175 640 x 480
42 0
Mode section polarity DOT CLOCK
[MHz] Resolution
H(Pixels) + 45 1650 1280 110 40 220
V(Lines) + 60 750 720 5 5 20
H(Pixels) - 49.702 1680 1280 72 128 200
V(Lines) + 59.81 831 800 3 6 22
H(Pixels) + 63.981 1688 1280 48 112 248
V(Lines) + 60.02 1066 1024 1 3 38
H(Pixels) + 60 1800 1600 24 80 96
V(Lines) + 60 1000 900 1 3 96
H(Pixels) + 67.5 2200 1920 88 44 148
V(Lines) - 60 1125 1080 4 5 36
H(Pixels) + 133.29 2080 1920 48 32 160
V(Li ) 60 2222 2160 54 5 3
10 277.25 1920 x
2160
8 108 1600 x 900
9 148.5 1920 x
1080
6 83.5 1280 x 800
7 108 1280 x
1024
5 74.25 1280 x 720
V(Lines) - 60 2222 2160 54 5 3
H(Pixels) + 88.79 2720 2560 48 32 80
V(Lines) - 59.95 1481 1440 3 5 33
H(Pixels) + 67.5 4400 3840 176 88 296
V(Lines) - 30 2250 2160 8 10 72
H(Pixels) + 135 4400 3840 176 88 296
V(Lines) - 60 2250 2160 8 10 72
l 12) è Recommended Timing (HDMI1.4) , HDMI ULTRA Deep Color : OFF
l 13) è Recommended Timing (HDMI2.0) , HDMI ULTRA Deep Color : ON
12 297 3840 x
2160
13 594 3840 x
2160
10 277.25 2160
11 241.5 2560 x
1440

- 7- Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
ADJUSTMENT INSTRUCTION
1.Application
1.1ThisdocumentisappliedtoLM8BAchassis27UK670_27BK67ULCDMonitorwhichismanufacturedinMonitorFactoryoris
producedonthebasisofthisdata.
1.2ManufacturingType:SET

2.Designation
2.1Theadjustmentisaccordingtotheorderwhichisdesignatedandwhichmustbefollowed,accordingtotheplanwhichcan
bechangedonlyonagreeing.
2.2.PowerAdjustment:FreeVoltage
2.3.MagneticFieldCondition:Nil.
2.4.InputsignalUnit:ProductSpecificationStandard
2.5.Reserveafteroperation:Above5Minutes(HeatRun)
Temperature:at25℃±5°C/Relativehumidity:65±10%/Inputvoltage:100~240V,50/60Hz
2.6.Adjustmentequipments:ColorAnalyzer(CA‐210orCA‐110),DDCAdjustmentJigequipment,

3.MainPCBcheckprocess(SMT)
*APC‐AfterManual‐Insult,executingAPC

3.1ADCProcess
‐27UK670_27BK67Udoesn’tneedADCprocessbecauseithasonlydigitalinputlikeDisplayPort,HDMI.

3.2MainPCBFunctiontest
‐Checkdisplay/audioaccordingtointerface
3.3WriteHDCP2.2Key
a.WriteHDCPKeyintoFlashmemorybyusingDDC2ABprotocol&HDCPAdjustmentJigequipment.
HDCP2.2WriteCommand:E9AddressHighAddressLowex)E90000
*Theremustbeinputsignal.NoinputsignalcausestheHDCPKeywritefail.
*HDCP1.4Keyisembeddedonscaler.


- 8- Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
4. TotalAssemblylineprocess

4.1EDIDSerialNumberWrite
‐ThismodelDON’TneedtowritefullediddataforupdatetheSerialnumber.
JustwritetheS/Ndatabyusingadjustmentcommand.
Send Serial data Send 24 byte
( EDID SN(4byte) + date (2byte) + Ascii SN(18byte) )
Read C/s of Serial data Read checksum data of 24 byte

4.2VerifyHDCPKey
CheckOSDwithagingonmodeorusingMasterSignalgeneratorwithHDCPOnandconnecttomonitorwithHDMI
IftheHDCPKeyisNG,thecolorofbackgroundwillbeRed,andifOK,itscolorwillbeWhiteasbelowpicture.
4.3SetAutomaticStandbytime
a.SetAutomaticStandbytimebyadjustmentjigequipment:Europe:4H,Others:OFF
Commandset:F70001(forEurope–set4h)
  F70000(forothers–set0ff)
b.ChecktheAutomaticStandbytimesettingvaluebyadjustmentjigequipment.
Pleasecheckthevalueof0xA60xEEaddress
  Value:0x00‐OFF
0x04‐Set4H

4.4Factorycalibration
a. FactoryCalibration(2.2):Gamma,dE,ColorTemperature(6500k)
‐ReferenceModel:27MU67/27UD68/27UD88/27UD58/27UD88/32UD89
‐Input:HDMI1/2,GrayPatternwithGammacorrectionusingcommandusing“AdjustmentCommand”
‐ThismodelmustbecalibratedGamma2.2
Gammacalibrationandverify


- 9- Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
※whendoingAdjustment,Pleasemakecircumstanceasbelow.



4.5Whitebalancecheck
‐.Beforethefactorycalibration,checktheWhitebalanceaccordingtobelowspecification.
HDMI1920x1080(or3840x2160),FullWhite
Tolerance:‐/+0.015/LuminanceSpec(min):280
Checkcondition:custommode(outgoingcondition)
AgingTime[min]xy
20.3190.339
40.3180.338
80.3180.337
100.3170.336
250.3160.333
400.3150.331
2550.3130.329

*Note:ManualW/Bprocess
1)WheninDCOffCondition
2)Pressleftbutton3‐timesandthenrightbutton1‐times,presspowerbutton
3)PressMenu(right‐sideofOSD)buttonandcanseeServiceMenu.

4.6CheckHDR(Don’tsupport)
‐.Beforethefactorycalibration,checktheWhitebalanceaccordingtobelowspecification.
1)HDRModecheck(HDMI)
‐.Equipment:MSPG‐7800
‐.CheckPoint:HDROSDbutthisOSDdisapperinfewseconds
 


- 10 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.

4.7DPMOperationcheck
■MeasurementCondition:100~240V@50/60Hz
1)SetInputtoDisplayPort,HDMI1,HDMI2,USBC
2)Turnoffthesourcedevice.
3)CheckDPMoperationrefertothebelowtable.

OperatingCondition
Sync(H/V)
orVideo
EUT
(MSPG6100)
LED(SET)Wattage(W)

Sleepmode(DPM)Off/OffOffOff0.5W
ForUSBC,OSDmenu
shouldbechangedto
DeepSleepModeOn.
Offmode‐‐Off0.3WDCSwitchOff


5.Shippingcondition
ÆMakesuretodoFACTORYRESETatthefinalprocess.
No. Item Content& Outgoing Condition 비고
Accessory Refer to BOM / And General
specification(3page)
Full accessory list is included
in general specification
2
Outgoing
Conditio
n
Quick
Settings
Brightness 85
Contrast 70
Volume 30
Color Temp Custom
Input Input List HDMI1 *Input Save ad last
condition
Aspect Ratio Full wide
Picture
Picture Mode Custom
Picture Adjust
Brightness 85
Contrast 70
Sharpness 50
Super Resolution+ Off
Black Level
Depending on input signal
(RGB: High)
(YUV: Low)
HDMI ULTRAHD Deep Color On
DFC Off
Game Adjust Response Time Fast
FreeSync Off

- 11 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
Black Stabilizer 50
Color Adjust
Gamma Mode 2
Color Temp Custom
Red 50
Green 50
Blue 50
Six Color (Hue/Saturation) 50
Picture Reset No
General
Language Depend on the sale region
Smart Energy Saving Low
Power LED Off
Automatic Standby Off(EU/EK/PD/EW/MA,4H)
DisplayPort1.2 Enable
Buzzer On
OSD Lock Off
OSD Size Small
Deep Sleep Mode Off
Information OK
Reset No


- 12 - Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
6.Signalcompositionforadjustment
6.1I2C(100KBPS)

6.2COMMUNICATIONSTART

START 6EASTOP50Ms 
#UntilACKBITgoesLOW,Repeatit.
6.3Commandform.
CommandformuseDDC2ABstandardcommunicationprotocol.
START6EA50ALENA03ACMDA00AVALACSASTOP
a.LEN:DATABYTEnumbertosend.
b.CMD:Commandlanguagethatmonitorexecutes.
c.VAL:FOSDATA
d.CS:Dada’sCHECHSUMthattransmit
e.DELAY:50MS
f.A:Acknowledge
6.4Screenadjustcommand(LENGTH=84) 
Adjustment contents CMD(hex) ADR VAL(hex) Explanation
EEPROM ALL INITIAL E4 00 00 adjustment Initialization
EEPROM READ E7 Slave add At EEPROM Read
EEPROM WRITE E8 Slave add Data Write data at EEPROM
R GAIN 16 00 00-64
Tune Gain
G GAIN 18 00 00-64
B GAIN 1A 00 00-64
BRIGHT(Backlight) 10 00 00-64 Tune Analog Bright
FACTORY RESET F0 00 00 Factory reset
AUTO_COLOR_ADJUST F1 00 0 AUTO COLOR Tuning
0:Auto color
COLOR_MODE_CHANGE F2 00
01 6500K
02 9300K
Elapsed time Clear E9 00 00 Aging off &Clear elapsed time
Aging On/Off F3 00 FF/00 FF:ON / 00:OFF
Input Select F4 00
0x90
0x91
0xD0
0x90 : HDMI1
0x91 : HDMI2
0xD0 : DP

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Only training and service purposes.
0xD1 0xD1 : Type-C
SYSTEM RESET F5 00 00 Restart System
Adjustment contents CMD(hex
) ADR VAL(hex) Explanation
Select Language 68 00
0x00 ~ 0x11
* 0x10 is not
available
00:English,
01: German
02: French
03: Spanish
04: Italian
05: Swedish,
06:Finnish
07: Portuguese
08: Brazil
09: Polish
0A: Russian
0B: Greek
0C: Ukrainian
0D: Chinese
0E:Japanese
0F: Korean
11 : Traditional Chinese
EDID SN UPDATE 0x77 0 0x00 Update all input’s serial data
APD command 0xF7 00 0x00~0x01 0x00:OFF
0x01: set APD time to 4h
Module selection F6
0x31:LM270WR3‐SSA1(Default)
0x36:MV270QUM‐N20
HDCP 2.2 write F9 00 00 Write HDCP 2.2 key
HDCP 2.2 read F8 data Read HDCP 2.2 key
Send Serial data 75 data Send 24 byte(EDID SN(4byte) +
date (2byte) + Ascii SN(18byte))
Read C/s of Serial data 76 data Read checksum data of 24 byte
HDR Max Bright B2 00 00
01
0x00 : OFF
0x01 : ON

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Only training and service purposes.

6.5.EEPROMDataWrite
6.5.1SiganlTABLE



LEN:84h+Bytes
CMD:E8h
ADH:E2PROMSlaveAddress(A0,A2,A4,A6,A8,AA,AC,AE),Not00h(ReservedbyBufferToEEPROM)
ADL:E2PROMSubAddress(00~FF)
Data:Writedata
Delay:20ms

6.5.2.CommandSet
No.AdjustmentcontentsCMD(hex)LENExplanation
1EEPROMWRITEE89416‐ByteWrite
2 (84+n)n‐byteWrite
*Use
FOSDefaultwrite:
<14modedata>write
SyncFlags,HPeriodH,HPeriodL,VtotalH,VtotalL,SrcHTotalH,SrcHTotalL
SrcHStartH,SrcHStartL,SrcVStartH,SrcVStartL,HsyncPhase
TemporaryDatawrite:WritetoparticularaddressofEEPROM.

6.6E2PROMDataRead
6.6.1SignalTABLE




‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐

128Bytes
6.6.2COMMANDSET
No.AdjustmentcontentsCMD(hex) ADH(hex) ADL(hex) Explanation
1EEPROMREADE7A000‐Page0~7FRead
2 800‐Page80~FFRead
3 A201‐Page0~7FRead
Dn ASTART 6F D1AASTOP
STOP
AAAAA 506E 03 CMD ADH84+nSTART ADL A
CS
A
AData_1 A. . . Data_n ADelay 20m
STOP
AAAAA506E 03 CMD ADH84START A AADL ACS
Delay 150ms

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Only training and service purposes.
4 801‐Page80~FFRead
5 A402‐Page0~7FRead
6 802‐Page80~FFRead
7 A603‐Page0~7FRead
8 803‐Page80~FFRead
9 A804‐Page0~7FRead
10 804‐Page80~FFRead
11 AA05‐Page0~7FRead
12 805‐Page80~FFRead
13 AC06‐Page0~7FRead
14 806‐Page80~FFRead
15 AE07‐Page0~7FRead
16 807‐Page80~FFRead
6.6.3Use
ReadE2PROM’sspecificareaasunitof128(80h)‐byte.(84h)
6.6.4EDIDWrite
EEPROMaccessbyusingDDC2Bprotocol
1‐Bytewrite
STOP
ALA0 DSTART AA
L:0x00~0x7F
D:data
8‐bytewrite
START A0 AL A Data1 A …. A A STOP
Data8
 L:0x00,0x10,….0x70
6.6.5EDIDRead
DDC2BCommand.(A0/A1)
START A0 A00 START A1 AData1 . . . Data128 ACS ASTOP

 ‐128BytetransferofEDIDBufferofMICOM

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Only training and service purposes.
BLOCK DIAGRAM
MST9U10Q1
SPI
UHD
Panel (3840 X 2160)
HDMI 1
DPRX, AUXN, HPD
HDMI 2
TS3DV642
(Switch)
Key1, Key2
DDR2
SDRAM
LED Driver IC
MP3378 Flash
Memory
(16MBIT)
TMDS // DDC // HPD Joystick
(Control Key)
DP
TS3DV642
(Switch)
USB Type-C
EDID
EEPROM (내장)
HP Out
L/R Out
HP AMP
USB Type A
(USB 3.0)
MUX DP Signal
PD Controller
DP, USB 3.0
USB HUB USB 3.0 UP
USB 2.0 DN for Billboard
CC communication
WLED_ENABLE
WLED_ADIM
Flash
Memory
(8MBIT)
SPI
( HDMI 2.0 )
E-DP
DC-DC
USB3.0 / 2.0 DN
VBUS=5V / 0.9A
Sub-Micom
(LPC11U68JBD48)
(DP1.2)
USB Type A
(USB 3.0)
I2C for Scaler FW update
USB 2.0 UP
I2C for PD Controller update
I2C for PD Controller control
I2C for Mux control
VBUS=5V / 0.9A
USB 2.0 DN

Copyright © LG Electronics Inc. All rights reserved.
Only training and service purposes.
- 17 -
EXPLODED VIEW
910
900
920
510
200
300
330
400
540
A3
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
310
500
520

- 18- LGE Internal Use OnlyCopyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
TROUBLE SHOOTING GUIDE
1. No Power
Replace X100
N
Check C701
Voltage Level (19V)
Check Power connector
OK? Replace Adapter
Y
N Y
Check IC703 Output
Voltage Level (3.3V)
Replace IC703 &
Recheck
Y
N
Check X100 Clock
27MHz
Check IC701, 702 Output
Voltage Level (5V)
Replace IC701, 702 &
Recheck
N
Y
Replace IC107 Flash
Memory
Y
Y
Check IC705 Output
Voltage Level (2.5V, 1.2V)
Replace IC705 &
Recheck
N

- 19- LGE Internal Use OnlyCopyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
2. No Screen on
Replace FFCable
N
Module Back Light On?
Check IC601, IC602
Replace LED Driver IC
Y
N
N
Check Panel Power 10V (L700)
Check IC700 Output 10V
Replace IC700 &
Recheck
Y
N
Check Panel eDP AUX
P300 (#9, 10, 36, 37)
Check IC300, IC303
Repair Main B/D
Y
N
Check FFC Cable for Damage or
Open Conductors
Check LED Driver Output
(P601, P602 -1, 2, 5, 6)
Replace T-Con Board or Module
Y
Check P201 (PIN No.69)
Replace G-SYNC Module
N
Check WLED_ENABLE High?
(IC601,IC602 27pin)
Y
Replace G-SYNC Module
N

- 20 - LGE Internal Use OnlyCopyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
3. No Video – HDMI
Replace the G-SYNC Module
Check input signal format
Is it supported?
Check JK102 for proper
connection or Damage Replace the Connector
N
Y
Check HDMI Cable for Damage or
Open Connector
Y
Check I2C Signal
(EDID) Replace the IC100
N
Y
Check IC102 AUX Signal
(#J1,H1) Replace the IC102
N
Y
Check IC103 AUX Signal
(#3,4) Replace the IC103
N
Y
Y