LG 49LX340H User manual

P/NO : MFL69152122 (1611-REV01)
CHASSIS : LA5CB
MODEL : 49LX340H 49LX340H-U*
LED TV
SERVICE MANUAL
Internal Use Only
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

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Only for training and service purposes
CONTENTS
CONTENTS .............................................................................................. 2
SAFETY PRECAUTIONS ........................................................................ 3
SERVICING PRECAUTIONS ................................................................... 4
SPECIFICATION ...................................................................................... 6
USB DOWNLOAD ................................................................................... 9
TROUBLESHOOTING GUIDE................................................................ 10
BLOCK DIAGRAM.................................................................................. 16
EXPLODED VIEW .................................................................................. 17

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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 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 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 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 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 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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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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Only for training and service purposes
SPECIFICATION
NOTE : Specifications and others are subject to change without notice for improvement .
1. Application range
This spec sheet is applied LED TV with LA5CB chassis
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 specification
4. General Specification
No Item Specication Result Remark
1. Receiving System ATSC / NTSC-M / 64 & 256 QAM
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 AC 100 ~ 240V 50/60Hz Mark : 110V, 60Hz (N.America)
4. Market NORTH AMERICA
5. Screen Size 60/65 inch Wide (1920 × 1080) FHD + 120Hz All models without HD models
42/43/49/55 inch Wide (1920 × 1080) FHD + 60Hz All models without HD models
28/32 inch Wide (1366 × 768) HD + 60Hz
6. Aspect Ratio 16:9
7. Tuning System FS
8. Module Direct HC275EXN-VSDP1 CSOT 28LX330C-UA
LC320DUE-FHA3 LGD 32LX340H-UA
LC320DXE-MGA3 LGD 32LX330C -UA
HC400DUN-VCKN5 INX 40LX340H-UA
LC420DUE-MGA3 LGD 42LX330C –UA, 42LX530S-UA
NC430EUN-AACR1 LGD 43LX310C-UA
LC430EUE-FHM3 LGD 43LX340H-UA
NC490EUN-AACR1 LGD 49LX310C-UA
LC490EUE-FHM3 LGD 49LX341C –UA, 49LX340H-UA
49LX540S-UA
LC550EUE-FHM3 LGD 55LX341C –UA, 55LX340H-UA,
55LX540S-UA
NC600EUF-VSCN1/3 Sharp 60LX341C-UA, 60LX540S-UA
LC650EUF-FHM3 LGD 65LX341C-UA, 65LX540S-UA
9. Operating Environment 1) Temp : 0 ~ 40 deg
2) Humidity : ~ 80 %
10. Storage Environment 1) Temp : -20 ~ 60 deg
2) Humidity : ~ 85 %

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Only for training and service purposes
5. Supported video resolutions
5.1. RGB Input (PC)
No Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed DDC
1. 640*350 31.46 70.09 25.17 EGA X
2. 720*400 31.46 70.08 28.32 DOS O
3. 640*480 31.46 59.94 25.17 VESA(VGA) O
4. 800*600 37.87 60.31 40.00 VESA(SVGA) O
5. 1024*768 48.36 60.00 65.00 VESA(XGA) O
6. 1152*864 54.34 60.05 81.62 VESA O
7. 1360*768 47.71 60.01 85.50 VESA (WXGA) O
8. 1280*1024 63.98 60.02 108.0 VESA (SXGA) O
9. 1920*1080 67.50 60.00 148.5 HDTV 1080P O
5.2. Component input(Y, CB/PB, CR/PR)
No Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed Remark
1. 720*480 15.73 60.00 13.513 SDTV ,DVD 480I
2. 720*480 15.73 59.94 13.500 SDTV ,DVD 480I
3. 720*480 31.50 60.00 27.027 SDTV 480P
4. 720*480 31.47 59.94 27.000 SDTV 480P
5. 1280*720 45.00 60.00 74.250 HDTV 720P
6. 1280*720 44.96 59.94 74.176 HDTV 720P
7. 1920*1080 33.75 60.00 74.250 HDTV 1080I
8. 1920*1080 33.72 59.94 74.176 HDTV 1080I
9. 1920*1080 67.50 60.00 148.500 HDTV 1080P
10. 1920*1080 67.432 59.94 148.352 HDTV 1080P
11. 1920*1080 27.00 24.00 74.250 HDTV 1080P
12. 1920*1080 26.97 23.976 74.176 HDTV 1080P
13. 1920*1080 33.75 30.00 74.250 HDTV 1080P
14. 1920*1080 33.71 29.97 74.176 HDTV 1080P

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Only for training and service purposes
5.3. HDMI Input 1 (PC/DTV)
No Resolution H-freq(kHz) V-freq.(Hz) Pixel clock(MHz) Proposed DDC
PC (DVI) DDC
1. 640*350 31.46 70.09 25.17 EGA X
2. 720*400 31.46 70.08 28.32 DOS O
3. 640*480 31.46 59.94 25.17 VESA(VGA) O
4. 800*600 37.87 60.31 40.00 VESA(SVGA) O
5. 1024*768 48.36 60.00 65.00 VESA(XGA) O
6. 1152*864 54.34 60.05 81.62 VESA O
7. 1360*768 47.71 60.01 85.50 VESA (WXGA) O
8. 1280*1024 63.98 60.02 108.0 VESA (SXGA) O
9. 1920*1080 67.50 60.00 148.5 HDTV 1080P O
DTV
1 720*480 31.50 60.00 27.027 SDTV 480P
2 720*480 31.47 59.94 27.00 SDTV 480P
3 1280*720 45.00 60.00 74.25 HDTV 720P
4 1280*720 44.96 59.94 74.176 HDTV 720P
5 1920*1080 33.75 60.00 74.25 HDTV 1080I
6 1920*1080 33.72 59.94 74.176 HDTV 1080I
7 1920*1080 67.50 60.00 148.50 HDTV 1080P
8 1920*1080 67.43 59.94 148.352 HDTV 1080P
9 1920*1080 27.00 24.00 74.25 HDTV 1080P
10 1920*1080 26.97 23.97 74.176 HDTV 1080P
11 1920*1080 33.75 30.00 74.25 HDTV 1080P
12 1920*1080 33.71 29.97 74.176 HDTV 1080P

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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
1. Power-up boot check
Check stand-by Voltage.
P401 5, 6pi n : +13.2V Ch eck 12p i n Power con nector Ma i n B/ D 13. 2V Line
Short Check
Check X101 clock
24 MHz Replace X101
Ch e c k P 401 PWR _ ON.
1p i n : 3. 3V
Replace Mstar(I C101) or Main board
Check Multi Voltage
P401 7, 8pi n : A 13. 2V Replace Power Board
Check DRV ON Control
P401 11 pin : High
Ch eck Pow er Boa rd
Ch eck IC405, I C404, I C400, Q 406
Output Voltage
IC405 : 3. 5V
IC404 : 1. 5V
IC400 : 1. 1V & 5V
Q 406 : 3. 3V
Replace IC405, IC404, I C400, Q 406
Re-d ow n load software.
Check stand-by Voltage
L 403 : +13. 2V Replace L 403
Check LVDS Power Voltage
Q 405 : 13. 2V Replace Q405
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board
Chan ge Module
ok
ok
ok
ok
ok
ok
ok
ok
okNo
No
ok
Replace Power board.
ok
No
No
No
No
No
No
No
No

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Only for training and service purposes
2. Digital/Analog TV Video
3. AV Video
Check RF Cable & Signal
Check Tuner 3.3V Power
L3701,L3704 Replace L3701,L3704
Check IF_P/N Signal
TU3700, 6/7 Pin
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board.
ok
ok
ok
No
No
No
Bad Tuner. Replace Tuner.
Check input signal format.
Is it supported?
Check AV Cable for damage
for damage or open conductor
Check JK4400,CVBS Signal Line
R242
ok
ok
ok
No Replace Jack
ok
Check CVBS_DET Signal
R4410 Replace R4410
No
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board.
No

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Only for training and service purposes
4. RGB Video
5. HDMI Video
Check input signal format.
Is it supported?
Check RGB Cable
for damage or open conductor.
Check P3300
R/G/B signal Line
ok
ok
ok
No Replace Jack
Check RGB_DET Signal Replace R3308
No
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board.
ok
No
Check inputsignal format.
Is it supported?
Check HDMI Cable conductors
for damage or open conductor.
Check EDID Downlaod
ok
ok
ok
No Replace the defective IC or re-download EDID data
Check HDMI Signal Check other set
If no problem, check signal line
ok
No
Check Mstar LVDS Output Replace Mstar(IC101) or Main Board.
ok
No
Replace Main Board
No
Check HDMI_DET (HPD) No Replace HDMI1 R802, R805, R803, R808, R809, Q800
HDMI2 R812, R813, R814
Check HDMI I2C Signal
ok
No Replace D800.D801
Check JK800, JK801 No Replace Jack
ok

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Only for training and service purposes
6. All Source Audio
Check the TV Speaker Menu
(Menu -> Audio -> TV Speaker)
On
ok
ok
Replace C5630, C5632,C5633, C5631, C5634,C5635
Check Connector & P5600 Replace connector
if found to be damaged.
ok
No
Check speaker resistance
and connector damage. Replace speaker.
ok
No
Off Toggle the Menu
Check AMP IC(IC5600) Power
13.2V, 3.3V
No Replace Amp IC(IC5600)
Check Output Signal P5600
1,2, 3, 4 pin.
No
Check Mstar AUDIO_MASTER_CLK
R123
No Replace Mstar(IC101) or Main Board.
ok
Check AMP I2C Line
R111,R112
No Check signal line. Or replace Mstar(IC101)
Replace Audio AMP IC(IC5600)
Check signal line,
L5603,L5604, L5605, L5606
ok
No

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Only for training and service purposes
7. Digital/Analog TV Audio
Check RF Cable & Signal
Check Tuner 3.3V Power
L3701,L3704 Replace L3701,L3704
Check IF_P/N Signal
TU3700, 6/7 Pin
Check Mstar LVDS Output
ok
ok
ok
No
No Bad Tuner. Replace Tuner.
8. AV/RGB Audio
Check AV Cable for damage
for damage or open conductor
Check JK4400 Signal Line
R4408, R4409
ok
ok
No Replace Jack
Follow procedure
‘7.All source audio’
trouble shooting guide.

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Only for training and service purposes
9. External Speaker Out
ok
ok
Check Output Signal JK3400
4,5 pin. Replace Phone Jack(JK3400)
ok
No
Check JK3400 Replace Phone Jack
if found to be damaged.
ok
No
Check External Speaker Replace External speaker.
ok
No
Check AMP IC(IC3400) Power 24V
L3400
No Replace L3400
Check AMP IC(IC3400) Output
L3401,L3402
No replace AMP IC(IC901)
Check Mstar External AUDIO output
C3401,C3402
No Replace Mstar(IC101) or Main Board.
ok
Check AMP IC(IC3400) Mute High
R3403, 4pin
No Check signal line. Or replace Mstar(IC101)

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Only for training and service purposes
BLOCK DIAGRAM

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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 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
910
200 400
800
540
810
521
530
820
700
121 350
120
LV1
A2 A10
Set + Stand