LG 49LX570H User manual

P/NO : MFL69175104 (1612-REV02)
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
LED TV
SERVICE MANUAL
Internal Use Only
CHASSIS : LA5CJ/LA5CG
MODEL : 49LX570H/560H
MODEL : 49LX570H/560H-U*

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Only for training and service purposes
CONTENTS
CONTENTS .............................................................................................. 2
SAFETY PRECAUTIONS ........................................................................ 3
SERVICING PRECAUTIONS ................................................................... 4
SPECIFICATION ...................................................................................... 6
USB DOWNLOAD ................................................................................... 8
TROUBLE SHOOTING GUIDE................................................................. 9
BLOCK DIAGRAM ................................................................................. 17
EXPLODED VIEW .................................................................................. 18

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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
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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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 conict between the
following servicing precautions and any of the safety precautions
on page 3 of this publication, always follow the safety precau-
tions. 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 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 specied 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 specied 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 specied 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 discharg-
ing 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 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 sol-
der removal devices not classied as “anti-static” can generate
electrical charges sufcient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufcient 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 elec-
trically 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 mate-
rial to the chassis or circuit assembly into which the device will
be installed.
CAUTION: Be sure no power is applied to the chassis or cir-
cuit, 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 appropri-
ate 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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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 remain-
ing 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 when-
ever 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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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 LA5CJ/
LA5CGchassis.
2. Requirement for Test
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.
3. Test method
1) Performance: LGE TV test method followed
2) Demanded other specification
- Safety : CE, IEC specification
- EMC : CE, IEC
4. Model General Specification
No. Item Specication Remarks
1 Receiving System ATSC / NTSC-M / 64 QAM / 256 QAM North America
2 Available Channel
1) VHF : 02~13
2) UHF : 14~69
3) DTV : 02-69
4) CATV : 01~135
5) CADTV : 01~135
3 Input Voltage North America AC 100 ~ 240V@
50/60Hz Mark : 110V, 60Hz (N.America)
4 Market North America
5 Screen Size 49 inch Wide (1920 × 1080) FHD + T120Hz
6 Aspect Ratio 16:9
7 Tuning System FS
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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Only for training and service purposes
5. Video resolutions
5.1. HDMI Input(PC/DTV)
No. Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed Remark
PC DDC
1640*350 31.468 70.09 25.17 EGA X
2720*400 31.469 70.08 28.32 DOS O
3640*480 31.469 59.94 25.17 VESA(VGA) O
4800*600 37.879 60.31 40.00 VESA(SVGA) O
51024*768 48.363 60.00 60.00 VESA(XGA) O
61152*864 54.348 60.053 VESA X
71280*1024 63.981 60.020 108.0 VESA (SXGA) O
81360*768 47.712 60.015 85.50 VESA (WXGA) O
91920*1080 67.50 60.00 148.5 HDTV 1080P O
DTV
1 720*480 31.500 60.000 27.027 SDTV 480P
2 720*480 31.470 59.940 27.000 SDTV 480P
3 1280*720 45.000 60.000 74.250 HDTV 720P
4 1280*720 44.960 59.940 74.176 HDTV 720P
5 1920*1080 33.750 60.000 74.250 HDTV 1080I
6 1920*1080 33.720 59.940 74.176 HDTV 1080I
7 1920*1080 67.500 60.000 148.500 HDTV 1080P
8 1920*1080 67.4320 59.940 148.352 HDTV 1080P
9 1920*1080 27.000 24.000 74.250 HDTV 1080P
10 1920*1080 26.970 23.976 74.176 HDTV 1080P
11 1920*1080 33.750 30.000 74.250 HDTV 1080P
12 1920*1080 33.710 29.970 74.176 HDTV 1080P
No. Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed Remark
PC DDC
1 640*350 31.468 70.09 25.17 EGA Х
2 720*400 31.469 70.08 28.32 DOS O
3 640*480 31.469 59.94 25.17 VESA(VGA) O
4 800*600 37.879 60.31 40.00 VESA(SVGA) O
5 1024*768 48.363 60.00 65.00 VESA(XGA) O
6 1280*768 47.776 59.870 79.5 CVT(WXGA) Х
7 1360*768 47.712 60.015 85.50 VESA (WXGA) Х
8 1600*1200 75.00 60.00 162.0 VESA (UXGA) X
9 1920*1080 67.50 60.00 148.5 HDTV 1080P O
5.2. RGB input(PC)

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Only for training and service purposes
(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, 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 files from memory”
(4) Updating is starting.
(5) Updating Completed, the TV will restart automatically.
(6) If your TV is turned on, check your updated version and Tool option. (explain the Tool option, next stage)
* If downloading version is more high than your TV have, TV can lost all channel data. In this case, you have to channel recover.
if all channel data is cleared, you didn’t have a DTV/ATV test on production line.
* After downloading, have to adjust Tool Option again.
(1) Push "IN-START" key in service remote control.
(2) Select "Tool Option 1" and push "OK" key.
(3) Punch in the number. (Each model has their number)
USB DOWNLOAD

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Only for training and service purposes
TROUBLE SHOOTING GUIDE
1. Power-Up Boot Fail Trouble Shooting guide
2. No OSD Trouble Shooting guide
Check P401 Voltage Level
(13.2V, L403)
Ch eck p ower co nnector and RL_ON
signalOK? Replace Power board
Y
N Y
Check IC5002
RESET an d UPDATE pin Check switch SW501, SW502
Y
N
Check X5000 Clock
32.768KHz
Check X5000 application circuit or
Replace X5000
Y
N
Check IC5002 IIC
communication state Check IIC line or replace IC5002
N
Check IR input state o f IC5002
57pin Check IR board
N
Y
Re-download PTC Micom
Y
Check LVDS Cable
Check LCD Module
Control board
Y
Replace Cable
N
Check P401 Voltage Level
(13.2V, L403)
Ch eck p ower co nnector and
RL_ON(p in1) signal OK ? Replace Power board
N Y
Check Q405 output Voltage(12V)
Y
Check Q405 app lication circuit or
replace Q405
N

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Only for training and service purposes
3. Analog RF Video Trouble Shooting guide
Check TU3001 Pin7(Video output)
Can you see the normal signal?
Ch eck tuner 5V p ower L3000
YES
NO Could you measure voltage of TU3001 & IIC lines?
Are th ey all normal?
Check Mstar LVDS output
NO You should check power line
& IIC lines.
YES
You should replace TUNER.
NO
Check IC5000
YES
YES
Ch eck tuner 3.3V p ower L3001 Replace L3001
NO Replace IC5000
Replace L3000
YES
NO
Ch eck tuner 1.8V p ower L3003 Replace IC3000 or IC3000
NO
Check RF cable & sig nal
YES
NO
Replace Mstar(IC101)
or main board

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Only for training and service purposes
4. Digital RF Trouble Shooting guide
Check RF Cable
Check IIC Signal
TU3001 #3, 4Pin Check IIC line and level shifter circuit
Y
N
Ch eck Tun er 5V Power
L3000 Check L3000
Y
N
Y
Check X201
and ap plication circuit
Check IF Signal
TU3001 #10, 11 Pin
Ch eck tun er ap plication circuit o r
replace tuner.
N
Y
Replace X201
N
Y
Replace IC101
Replace IC5000
N
YReplace L3000

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Only for training and service purposes
5. AV Video Trouble Shooting guide
Check JK5001
Can you see the normal waveform?
N
JK5001 may have problem. Replace this Jack.
Check the input of Mstar(IC101).
Measure waveform at C227 because it’s more easy to check.
Can you see the normal waveform?
YThis board has big problem
because Main chip (Mstar) have some troubles.
After checking thoroughly all path once again,
You should decide to replace Mstar or not.
Y
Check input signal is supported format
Y
Check AC cable for damage or open conductor
Y

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Only for training and service purposes
6. HDMI Video Trouble Shooting guide
Check JK800/JK801/JK802
Can you see the normal waveform?
N
JK800/JK801/JK802 may have problem. Replace this Jack.
This board has big problem because Main chip (Mstar) have some troubles.
After checking thoroughly all path once again, You should decide to replace Mstar or not.
Check input signal format.
Is it supported?
Y
Check AC cable for damage
For damage or open conductor
Y
Y
Check HDMI Switch IC Power
Check L800(3.3V, Not stand-by mode)
Y
Swap HDMI Switch IC,
is there same Problem?
Y
N
Replace L800

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Only for training and service purposes
7. RGB-PC Video Trouble shooting guide
8. Analog RF Audio Trouble Shooting guide
Check P3300
Can yo u see the normal waveform?
NO
P3300 may have problem. Replace this Jack.
Check the input of Mstar(IC101).
Measure waveform at R234, R235
because it’s more easy to check.
Can yo u see the normal waveform?
YES This board has big problem
because Main chip (Mstar) have some troubles.
After checking thoroughly all path once again,
You should d ecide to replace Mstar or not.
YES
Check input signal format.
Is it supported?
YES
Check AC cable for damage
For damage or open conductor
YES
Check RF Cable & Sign al
Check Audio AMP output
L5503,L5504,L5505,L5506
Y
Check TU3001 Pin1 (SIF Output)
Can you see the no rmal signal?
Y
Could you measure voltage of TU3001& IIC lines?
Are th ey all normal?
NYou should check power line & IIC lines.
N
You should replace TUNER.
Y
Check IC5600
Y
Replace IC5600
N
Replace L5503,L5504,L5505,L5506
N
Ch eck th e in put o f Mstar (IC101).
Measure wavefo rm at C115, C116 because it’s more easy to
check.
Can you see the no rmal waveform?
Y
After checking audio signal line, you should decide to replace item or not.
N

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Only for training and service purposes
9. AV/RGB-PC Audio in Trouble shooting guide
Check input signal format.
Is it supported?
Check P3300, JK5001
Can you see the normal waveform? Replace P3300, JK5001
Y
N
Check AC cable for damage
For damage or open conductor
Y
Y
Check the input of Mstar(IC101).
Measure waveform at C209, C211 because it’s more easy to check.
Can you see the normal waveform?
Y
Check Audio AMP output
L5503,L5504,L5505,L5506
Y
Replace L5503,L5504,L5505,L5506
N
This board has big problem because Main chip (Mstar) have some troubles.
After checking thoroughly all path once again, You should decide to replace Mstar or not.

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Only for training and service purposes
10. HDMI Audio in Trouble Shooting guide
11. Audio out Trouble shooting guide
Check input signal format.
Is it supported?
Check JK800/JK801/JK802
Can you see the normal waveform? Replace JK800/JK801/JK802
Y
N
Check AC cable for damage
For damage or open conductor
Y
Y
Check Audio AMP output
L5503,L5504,L5505,L5506
Y
Replace L5503,L5504,L5505,L5506
N
This board has big problem because Main chip (Mstar) have some troubles.
After checking thoroughly all path once again, You should d ecide to replace Mstar or not.
Check the output o f Mstar(IC101).
Measure waveform at R123, IC5600(Pin 23, 24).
because it’s more easy to check. Can you see the n ormal signal?
YES
NO This board has big problem because Main chip (MStar) have some troubles.
After checking thoroughly all path once again,
You sho uld decide to replace Mstar or not.
Check Audio AMP outp ut L5503,L5504,L5505,L5506
Can you see the n ormal waveform?
NO
YES
After checking the Power & I2C & Reset of th is ch ip,
you should decide to replace th isor n ot.
Ch eck th e sp eaker o utput wafer P5600.
Can you see the n ormal waveform?
NO
YES
After checking audio signal line, you sh ould decide to replace item or not.
Ch eck th e co nnector & Speaker

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Only for training and service purposes
BLOCK DIAGRAM

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Only for training and service purposes
900
910
200 400
800
540
810
521
530
820
700
121 350
120
LV1
A2 A10
Set + Stand
EXPLODED VIEW
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