LG RH-2320 User manual

Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
CONTENTS
SECTION 1.........SUMMARY
SECTION 2.........CABINET & MAIN CHASSIS
SECTION 3.........ELECTRICAL
SECTION 4.........RS-06A LOADER PART
SECTION 5.........REPLACEMENT PARTS LIST

1-2 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SECTION 1
SUMMARY
CONTENTS
NEW FUNCTIONS OF HDD/DVD RECORDER .................................................................................1-3
PRODUCT SAFETY SERVICING GUIDELINES FOR HDD/DVD RECORDER PRODUCTS ..............1-4
SERVICING PRECAUTIONS....................................................................................................................1-5
• GENERAL SERVICING PRECAUTIONS
• INSULATION CHECKING PRODEDURE
• ELECTROSTATICALLY SENSITIVE (ES) DEVICES
SERVICE INFORMATION FOR EEPROM IC SETTING..................................................................1-6
UPGRADE THE MAIN & LOADER PROGRAM.................................................................................1-7
SPECIFICATIONS ........................................................................................................................................1-8

1-3
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
NEW FUNCTIONS OF HDD/DVD RECORDER
• HDMI
HDMI IS THE SPECIFICATION FOR THE HIGH-DEFINITION MULTIMEDIA INTERFACE. HDMI IS PROVIDED
FOR TRANSMITTING DIGITAL TELEVISION AUDIOVISUAL SIGALS FROM HDD-DVD RECODER TO TELE-
VISION SETS, OTHER VIDEO DISPLAYS. HDMI CAN CARRY HIGH QUALITY MULTI-CHANNEL AUDIO DATA
AND CAN CARRY ALL STANDARD AND HIGH DEFINITION CONSUMER ELECTRONICS VIDEO FORMATS.
CONTENT PROTECTION TECHNOLOGY IS AVAILABLE. HDMI CAN ALSO CARRY CONTROL AND STATUS
INFORMATION IN BOTH DIRECTIONS.
<< OPERATING >>
AUDIO, VIDEO AND AUXILIARY DATA IS TRANSMITTED ACROSS THE THREE TMDS DATA CHANNELS.
THE VIDEO PIXEL CLOCK IS TRANSMITTED ON THE TMDS CLOCK CHANNEL AND USED BY THE
RECEIVER AS A FREQUENCY REFERENCE FOR DATA RECOVERY ON THE THREE TMDS DATA CHAN-
NELS.
VIDEO DATA IS CARRIED AS A SERIES OF 24-BIT PIXELS ON THE THREE TMDS DATA CHANNELS.
TMDS ENCODING CONVERTS THE 8BIT PER CHANNEL INTO THE 10BIT DC-BALANCED.
VIDEO PIXEL RATES CAN RANGE FROM 25MHz TO 165MHz. THE VIDEO PIXELS CAN BE ENCODED IN
EITHER RGB, YCbCr 4:4:4 OR YCbCr 4:2:2 FORAMTS. IN ALL THREE CASES, UP TP 24 BITS PER PIXEL
CAN BE TRANSFERRED.
FAST DUBBING
DUBBING MEANS A COPYING FUNCTION BETWEEN HDD TO DVD DISCS.
COPYING BETWEEN HDD TO DVD IS A COMPLETELY DIGITAL PROCESS AND THEREFORE INVOLVES
NO LOSS OF QUALITY IN THE AUDIO OR VIDEO. SO THIS MEANS THAT COPYING CAN BE CARRIED OUT
AT THE MAXIMUM SPEED POSSIBLE.
<< DUBBING SPEED RATE >>
NORMAL DUBBING : SPEED RATE MAX X1
FAST DUBBING : SPEED RATE MAX X4
WHEN FAST DUBBING FROM HDD TO DVD, THE SPEED OF COPYING DEPENDS ON THE RECODING
MODE AND THE KIND OF USING THE DVD DISC, AND THIS MODE IS NOT AVAILABLE FOR EDITED VIDEO
TITLE IN HDD.
WHEN FAST DUBBING FROM DVD TO HDD, ONLY AVAILABLE WHEN COPYING VR MODE DISC(DVD-RW)
TO HDD, AND ONLY NORMAL DUBBING AVAILABLE WHEN COPYING VIDEO MODE DISC(DVD+RW/RW,
DVD-R) TO HDD.

1-4 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
PRODUCT SAFETY SERVICING GUIDELINES FOR HDD/DVD RECORDER PRODUCTS
IMPORTANT SAFETY NOTICE
This manual was prepared for use only by properly trained audio-video service tech-
nicians.
When servicing this product, under no circumstances should the original design be
modified or altered without permission from LG Corporation. All components should
be replaced only with types identical to those in the original circuit and their physical
location, wiring and lead dress must conform to original layout upon completion of
repairs.
Special components are also used to prevent x-radiation, shock and fire hazard.
These components are indicated by the letter “x” included in their component desig-
nators and are required to maintain safe performance. No deviations are allowed
without prior approval by LG Corporation.
Circuit diagrams may occasionally differ from the actual circuit used. This way, imple-
mentation of the latest safety and performance improvement changes into the set is
not delayed until the new service literature is printed.
CAUTION : Do not attempt to modify this product in any way. Never perform cus-
tomized installations without manufacturer’s approval. Unauthorized modifications will
not only void the warranty, but may lead to property damage or user injury.
Service work should be performed only after you are thoroughly familiar with these
safety checks and servicing guidelines.
GRAPHIC SYMBOLS
The exclamation point within an equilateral triangle is intended to alert
the service personnel to important safety information in the service lit-
erature.
The lightning flash with arrowhead symbol within an equilateral trian-
gle is intended to alert the service personnel to the presence of non-
insulated “dangerous voltage” that may be of sufficient magnitude to
constitute a risk of electric shock.
The pictorial representation of a fuse and its rating within an equilater-
al triangle is intended to convey to the service personnel the following
fuse replacement caution notice:
CAUTION : FOR CONTINUED PROTECTION AGAINST RISK OF
FIRE, REPLACE ALL FUSES WITH THE SAME TYPE AND RAT-
ING AS MARKED NEAR EACH FUSE.
SERVICE INFORMATION
While servicing, use an isolation transformer for protection from AC line shock. After
the original service problem has been corrected, make a check of the following:
FIRE AND SHOCK HAZARD
1. Be sure that all components are positioned to avoid a possibility of adjacent com-
ponent shorts. This is especially important on items trans-ported to and from the
repair shop.
2. Verify that all protective devices such as insulators, barriers, covers, shields, strain
reliefs, power supply cords, and other hardware have been reinstalled per the orig-
inal design. Be sure that the safety purpose of the polarized line plug has not been
defeated.
3. Soldering must be inspected to discover possible cold solder joints, solder splash-
es, or sharp solder points. Be certain to remove all loose foreign particles.
4. Check for physical evidence of damage or deterioration to parts and components,
for frayed leads or damaged insulation (including the AC cord), and replace if nec-
essary.
5. No lead or component should touch a high current device or a resistor rated at 1
watt or more. Lead tension around protruding metal surfaces must be avoided.
6. After reassembly of the set, always perform an AC leakage test on all exposed
metallic parts of the cabinet (the channel selector knobs, antenna terminals, han-
dle and screws) to be sure that set is safe to operate without danger of electrical
shock. DO NOT USE A LINE ISOLATION TRANSFORMER DURING THIS
TEST. Use an AC voltmeter having 5000 ohms per volt or more sensitivity in the
following manner: Connect a 1500 ohm, 10 watt resistor, paralleled by a .15 mfd
150V AC type capacitor between a known good earth ground water pipe, conduit,
etc.) and the exposed metallic parts, one at a time. Measure the AC voltage across
the combination of 1500 ohm resistor and .15 mfd capacitor. Reverse the AC plug
by using a non-polarized adaptor and repeat AC voltage measurements for each
exposed metallic part. Voltage measured must not exceed 0.75 volts RMS. This
corresponds to 0.5 milliamp AC. Any value exceeding this limit constitutes a poten-
tial shock hazard and must be corrected immediately.
TIPS ON PROPER INSTALLATION
1. Never install any receiver in a closed-in recess, cubbyhole, or closely fitting shelf
space over, or close to, a heat duct, or in the path of heated air flow.
2. Avoid conditions of high humidity such as: outdoor patio installations where dew
is a factor, near steam radiators where steam leakage is a factor, etc.
3. Avoid placement where draperies may obstruct venting. The customer should also
avoid the use of decorative scarves or other coverings that might obstruct ventila-
tion.
4. Wall- and shelf-mounted installations using a commercial mounting kit must follow
the factory-approved mounting instructions. A product mounted to a shelf or plat-
form must retain its original feet (or the equivalent thickness in spacers) to provide
adequate air flow across the bottom. Bolts or screws used for fasteners must not
touch any parts or wiring. Perform leakage tests on customized installations.
5. Caution customers against mounting a product on a sloping shelf or in a tilted posi-
tion, unless the receiver is properly secured.
6. A product on a roll-about cart should be stable in its mounting to the cart.
Caution the customer on the hazards of trying to roll a cart with small casters
across thresholds or deep pile carpets.
7. Caution customers against using extension cords. Explain that a forest of exten-
sions, sprouting from a single outlet, can lead to disastrous consequences to
home and family.

1-5
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SERVICING PRECAUTIONS
CAUTION: Before servicing the HDD / DVD RECORDER cov-
ered by this service data and its supplements and addends,
read and follow the SAFETY PRECAUTIONS. NOTE: if
unforeseen circumstances create conflict between the follow-
ing servicing precautions and any of the safety precautions in
this publications, always follow the safety precautions.
Remember Safety First :
General Servicing Precautions
1. Always unplug the HDD / DVD RECORDER AC power cord
from the AC power source before:
(1) Removing or reinstalling any component, circuit board,
module, or any other assembly.
(2) Disconnecting or reconnecting any internal electrical
plug or other electrical connection.
(3) Connecting a test substitute in parallel with an electrolyt-
ic capacitor.
Caution : A wrong part substitution or incorrect polarity
installation of electrolytic capacitors may result in an
explosion hazard.
2. Do not spray chemicals on or near this HDD / DVD
RECORDER or any of its assemblies.
3. Unless specified otherwise in this service data, clean elec-
trical contacts by applying an appropriate contact cleaning
solution to the contacts with a pipe cleaner, cotton-tipped
swab, or comparable soft applicator.
Unless specified otherwise in this service data, lubrication of
contacts is not required.
4. Do not defeat any plug/socket B+ voltage interlocks with
whitch instruments covered by this service manual might be
equipped.
5. Do not apply AC power to this HDD / DVD RECORDER and
/ or any of its electrical assemblies unless all solidstate
device heat sinks are correctly installed.
6. Always connect the test instrument ground lead to an appro-
priate ground before connecting the test instrument positive
lead. Always remove the test instrument ground lead last.
Insulation Checking Procedure
Disconnect the attachment plug from the AC outlet and turn
the power on. Connect an insulation resistance meter (500V)
to the blades of the attachment plug. The insulation resistance
between each blade of the attachment plug and accessible
conductive parts (Note 1) should be more than 1Mohm.
Note 1 : Accessible Conductive Parts include Metal panels,
Input terminals, Earphone jacks,etc.
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 electricity.
1. Immediately before handling any semiconductor component
or semiconductor-equipped assembly, drain off any electro-
static charge on your body by touching a known earth
ground. Alternatively, obtain and wear a commercially avail-
able discharging wrist strap device, which should be
removed for 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 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
an electrical charge 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 cir-
cuit, and observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Normally harmless motion such
as the brushing together of your clothes fabric or the lifting
of your foot from a carpeted floor can generate static elec-
tricity sufficient to damage an ES device.)

1-6 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SERVICE INFORMATION FOR EEPROM IC SETTING
1. Please the CLEAR button on the remocon together with OPEN the Front Panel about 6 sec.
The picture on OSD will be bellow ;
Model : RH3'S
2. To MOVE from OP! to another option. Please button on the remote control.
3. To CHANGE the Option Code. Please button on the remote control.
4. To APPLY the Option Code. After change the option press ENTER button on remote control.
5. To INITIALIZE the system. Press CLEAR button on the remotecontrol together with OPEN on the Front panel
about 2sec.
6. To exit from the Option Code menu without Initialize the system.
Just turn off the power and turn on again.
Disc Read Time
DVD 018 Sec OK
CD 021 Sec NG
OP1 : 00 00000000 M : 10.013
OP2 : 00 00000000 E : FF(OR)
OP3 : 00 00000000
OP4 : 00 00000000
OP5 : 00 00000000
OP6 : 00 00000000
OP7 : 00 00000000 Write : OK
OP8 : 00 00000000 E x i t : MP
OP9 : 00 00000000 Move : < >
OPA : 00 00000000 E d i t :

1-7
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
UPGRADE THE MAIN & LOADER PROGRAM
1. MAKING UPGRADE DISC
1) Do Physical format as ISO9660 or JOLIET file
system
2) Don’t care about the CD Volume label
3) Write RH300 B_E & LOADER file on Root
4) Write I_O file on Root
Note) You can’t write steps 3 and 4 on the same disc.
Use the different disc to write another step.
* OPTIONAL PARTS
1) B_E
LG_RH300_UPDATE_PAL.ROM
2) LOADER
DvdS617.rs6, Yas617.din
3) I_O
io_micom_update.hex
2. UPGRADE FLASH (MAIN & LOADER) and I_O
1) Put Upgrde DISC on the Set
2) After Disc Reading, You can see below screen
* OPTIONAL PARTS
1) MAIN
ONLY B_E UPGRADE
2) LOADER
ONLY LOADER UPGRADE
3) ALL
B_E & LOADER UPGRADE
3) Press ENTER (or OK) KEY.
You can see both current and upgrade version.
4) Press PLAY KEY.
Start upgrading.
5) After upgrading, Automatically open tray.
Eject the Disc.
Reboot the Set
6) Put I_O update disc and repeat 1) ~ 5)

1-8 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SPECIFICATIONS
• GENERAL
Power requirements AC 200-240V, 50/60 Hz
Power consumption 30W
Dimensions (approx.) 430 X 49 X 275mm (w x h x d) without foot
Net weight (approx.) 4kg
Operating temperature 5°C to 35°C
Operating humidity 5% to 65%
Television system PAL I, B/G, I/I, SECAM D/K, K1 color system
Recording format PAL
• RECORDING
Recording format DVD Video Recording, DVD-VIDEO
Recordable media HDD (320GB), DVD-RW, DVD-R, DVD+RW,
DVD+R, DVD+R (Double Layer), DVD-RAM
Recordable time DVD (4.7GB): Approx. 1 hour (XP mode),
2 hours (SP mode), 4 hours (LP mode),
6 hours (EP mode), 14 hours (MLP mode)
DVD+R DL (8.5GB): Approx. 3hours (XP mode),
3.8 hours (SP mode), 7.3 hours (LP mode),
9.1 hours (EP mode), 21 hours (MLP mode)
HDD (320GB, MPEG2 Recording):
Approx. 85 hours (XP mode), 165 hours (SP mode),
323 hours (LP mode), 456 hours (EP mode),
935 hours (MLP mode)
Video recording format
Sampling frequency 27MHz
Compression format MPEG2 (VBR supported)
Audio recording format
Sampling frequency 48kHz
Compression format Dolby Digital
• PLAYBACK
Frequency response DVD (PCM 48kHz): 8Hz to 22kHz,
CD: 8Hz to 20kHz
DVD (PCM 96kHz): 8Hz to 44kHz
Signal-to-noise ratio More than 90dB (AUDIO OUT connector)
Harmonic distortion Less than 0.02% (AUDIO OUT connector)
• INPUTS
Dynamic range More than 95dB (AUDIO OUT connector)
ANTENNA IN Antenna input, 75ohms
VIDEO IN 1.0 Vp-p 75ohms, sync negative, RCA jack x 1 / SCART x 2
AUDIO IN 2.0 Vrms more than 47kohms, RCA jack (L, R) x 1 / SCART x 2
DV IN 4 pin (IEEE 1394 standard)
USB IN 4 pin (USB 1.1 standard)
• OUTPUTS
VIDEO OUT 1Vp-p 75Ω, sync negative, SCART x 2
S-VIDEO OUT (Y) 1.0V (p-p), 75Ω, sync negative,
Mini DIN 4-pin x 1(C) 0.3V (p-p) 75Ω
COMPONENT VIDEO OUT (Y) 1.0V (p-p), 75Ω, sync negative,
RCA jack x 1, (PB)/(PR) 0.7V (p-p), 75Ω, RCA jack x 2
HDMI video/audio output 19 pin (HDMI standard, Type A)
Audio output (digital audio) 0.5V (p-p), 75Ω, RCA jack x 1
Audio output (optical audio) 3V (p-p), Optical connector x 1
Audio output (analog audio) 2Vrms (1kHz, 0dB), 600Ω, RCA jack (L, R) x 2 / SCART x 2

2-1
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SECTION 2
CABINET & MAIN CHASSIS
CONTENTS
EXPLODED VIEWS .....................................................................................................................................2-2
1. CABINET AND MAIN FRAME SECTION ..................................................................................................2-2
2. DECK MECHANISM SECTION (RS-06A).................................................................................................2-3
3. PACKING ACCESSORY SECTION...........................................................................................................2-4

2-2 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SVC purchase order caution
Key board is array coming timer board.
Purchase order board separately supply
incomprehensible.
Supply is possible in Location No A50
state in exploded views.
OPTIONAL PARTS
463 462
250
462 463
463 462
A
468
A47
SMPS
A54A
253
HDMI BOARD
CABLE7
468
468
C
468
G
I/O BOARD
260
261
261
264
465
470
465
465
320
A44
468
B
A46
MAIN BOARD
471
468
C
E
D
B
A
CABLE6
468
261
261
CABLE5
CABLE10
G
104
F
A53
CABLE11
F
E
468
410
101
261
A26
273
468
468
261
A52
300
A43
CABLE1
452
KEY
452
275 452
275
452
D
A50
TIMER
280
285
286
281
A43A
274
CABLE2
279
J
468
468
A41
J
CABLE12
KARAOKE
A54
EXPLODED VIEWS
1. CABINET AND MAIN FRAME SECTION

2-3
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
2. DECK MECHANISM SECTION (RS-06A)
Main C.B.A
OPTIONAL PART
1018
1019
DR-11H : IN, SH ONLYDR-11H : PT ONLY
1043 1045
A005 1043 1045
1044
1042
A005
1018
1019
1431
1434
1437
1025
1432
1432
1041
1002
A001
A002
A46A
1033
1034
1032
1020
1439
1046
1047
1011
1013
1017
1433
1026
1016
1015
1012
1038
1432
1036
1001
1003
RS-06A(DR-11H)
1030

2-4 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
3. PACKING ACCESSORY SECTION
808 Battery
900 Remote Control
803 Packing
803 Packing
802 Box
OPTIONAL PARTS
810 Accessory Assembly
804 Bag
832 Disc
821 SCART Cable
806 RCA Plug(Black)
801Instruction Ass'y
820 RCA Plug(Yellow)
811Plug Ass'y 1way
812Plug Ass'y 2way
813Plug Ass'y 3way
823 HDMI Cable

3-1
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
SECTION 3
ELECTRICAL
CONTENTS
ELECTRICAL TROUBLESHOOTING GUIDE ...........3-2
1. POWER SUPPLY ON SMPS BOARD .............3-2
2. POWER SUPPLY ON I/O BOARD ...................3-4
3. SYSTEM CIRCUIT PART ..................................3-9
4. DISC NOT RECOGNIZED.................................3-9
5. WHEN PLAYING DISC, NO AUDIO OUTPUT ..........3-10
6. NO OPTICAL/DIGITAL OUTPUT ....................3-11
7. NO TUNER AUDIO OUTPUT .........................3-12
8. NO EXTERNAL AUDIO INPUT.......................3-13
9. NO RGB/COMPONENT VIDEO SIGNAL
WHEN PLAY DISC ...........................................3-14
10. NO COMPOSITE/S-VIDEO SIGNAL
WHEN PLAY DISC............................................3-15
11. NO TV, EXTERNAL INPUT VIDEO
SIGNAL..............................................................3-16
12. NO DV (IEEE1394)
INPUT (VIDEO/AUDIO) SIGNAL.....................3-17
WAVEFORMS..........................................................3-18
1. SMPS BLOCK ..................................................3-18
2. SYSTEM BLOCK .............................................3-20
3. VIDEO BLOCK (COLOR BAR INPUT)...........3-23
4. AUDIO BLOCK (1kHz SINEWAVE INPUT)....3-24
5. SERIAL INTERFACE BLOCK
(BETWEEN MAIN AND I/O) ............................3-25
6. TUNER BLOCK ................................................3-26
7. HDMI BLOCK ...................................................3-27
WIRING CONNECTION DIAGRAM...............3-28
1. WIRING CONNECTION DIAGRAM 1 ............3-28
2. WIRING CONNECTION DIAGRAM 2 ............3-29
3. WIRING CONNECTION DIAGRAM 3 ............3-30
BLOCK DIAGRAMS.............................................3-31
1. VERALL BLOCK DIAGRAM............................3-31
2. SMPS BLOCK DIAGRAM ...............................3-32
3. POWER MAIN BLOCK DIAGRAM .................3-33
4. POWER I/O BLOCK DIAGRAM......................3-34
5. A/V BLOCK DIAGRAM ....................................3-35
6. AUDIO OUT BLOCK DIAGRAM .....................3-36
7. HDMI BLOCK DIAGRAM ................................3-37
CIRCUIT DIAGRAMS...........................................3-39
1. SMPS 1 CIRCUIT DIAGRAM..........................3-39
2. SMPS 2 CIRCUIT DIAGRAM..........................3-41
3. MPEG CIRCUIT DIAGRAM.............................3-43
4. FLASH/DDR/DV CIRCUIT DIAGRAM............3-45
5. ATAPI, HDMI & USB CIRCUIT DIAGRAM .....3-47
6. I/O, µ-COM CIRCUIT DIAGRAM ....................3-49
7. DECODER & MIC CIRCUIT DIAGRAM.........3-51
8. SCART/RCA CIRCUIT DIAGRAM ..................3-53
9. HDMI CIRCUIT DIAGRAM ..............................3-55
10. TIMER CIRCUIT DIAGRAM (8 & 9 TOOLS) ...3-57
11. KEY CIRCUIT DIAGRAM (8 & 9 TOOLS) ......3-59
• CIRCUIT VOLTAGE CHART ....................3-61
PRINTED CIRCUIT BOARD DIAGRAMS...3-65
1. MAIN P.C.BOARD ............................................3-65
2. I/O P.C.BOARD.................................................3-67
3. POWER P.C.BOARD .......................................3-71
4. TIMER & KEY P.C.BOARD..............................3-73
5. HDMI P.C.BOARD ............................................3-75
6. KARAOKE P.C.BOARD ...................................3-75

3-2 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
Is the D127 normal?
ELECTRICAL TROUBLESHOOTING GUIDE
1. POWER SUPPLY ON SMPS BOARD
No 5.3VA
YES
Is the F101 normal? Replace the F101 (Use the same fuse)
YES
NO
Is the BD101 normal? Replace the BD101
YES
NO
Is the TH01 normal? Replace the TH01
YES
NO
Is the Vcc
(10V - 17V) supplied to
IC101 Pin 6?
Is the D102 normal?
YES
NO
NO
Check or replace the D102
Is the D128 normal? Replace the D128
YES
NO
Is there about 2.5V at the
IC103 Pin 1? Replace the IC103
YES
NO
Is the D121 normal? Replace the D121
YES
NO
Is the D122 normal? Replace the D122
YES
NO
Is the D125 normal? Replace the D125
YES
NO
Is the D124 normal? Replace the D124
YES
NO
Replace the D127
YES
NO
Is the D126 normal? Replace the D126
YES
NO
Power line of I/O PCB is short

3-3
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
No 5V for HDD & DVD drive
Is there about 5.5V at
the IC156 Pin 1? Check D125 and replace
YES
YES
NO
Is there about 4V ~ 5V at
the IC156 Pin 4?
Check the “PWR CTL‘H’”
signal from µ-COM
YES
NO
Check the IC156 and replace
No 12V for HDD & DVD drive
Is there about 13.5V at
the IC155 Pin 1? Check D124 and replace
YES
YES
NO
Is there about 4V ~ 5V at
the IC155 Pin 4?
Check the “PWR CTL ‘H’”
signal from µ-COM
YES
NO
Check the IC155 and replace

3-4 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
No 12VT
2. POWER SUPPLY ON I/O BOARD
Check D124 on SMPS
board and replace
YES
YES
NO
Is the Vcc (14V) supplied to
Q164 collector?
Check Q164 and replace
YES
NO
Is there about 12.5V at
ZD151 & Q164 base?
Check D126 on SMPS
board and replace
YES
NO
Is the Vcc (33V) supplied
to Q162 emiter?
Check Q162 and replace
YES
NO
Is there about 0V at
Q162 base?
Check the “TIMER_H”
signal from µ-COM
YES
NO
Is there about 5V at R170
and 0.7V at Q156 base?
Check Q156 and replace

3-5
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
No 5VT
Check Q152 and replace
Is the Vcc (5.3V)
supplied to Q155 emiter? Check 5.3VA on SMPS board
YES
YES
NO
Is there about 0V
at D152 and
Q152 vollector?
Check Q155 and replace
YES
NO
Is there about 5V
at R180 and 0.7V
at Q152 base?
Check the “TIMER H”
signal from µ-COM
YES
NO
No 33VT
Check Q152 and replace
Is the Vcc (33V)
supplied to Q161 emiter?
Check D126 on SMPS
board and replace
YES
YES
NO
Is there about 0V at
Q152 collector? Check Q161 and replace
YES
NO
Is there about 5V
at R180 and 0.7V
at Q152 base?
Check the “TIMER H”
signal from µ-COM
YES
NO

3-6 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
No 5.0VD
Is there about 5.3V at
the IC153 Pin 1? Check 5.3VA on SMPS board
YES
YES
NO
Is there about 4V ~ 5V at
the IC153 Pin 4?
Check the “PWR CTL H”
signal from µ-COM
YES
NO
Check the IC153 and replace
No 2.5V
Is there about 3V ~ 3.8V
at the IC151 Pin 1?
Check D154 and
D127 on SMPS board
YES
YES
NO
Is there about 4V ~ 5V at
the IC151 Pin 4?
Check the “PWR CTL H”
signal from µ-COM
YES
NO
Check the IC151 and replace
No 3.3V
Is there about 3.8V at
the IC152 Pin 1?
Check D127 on SMPS
board and replace
YES
YES
NO
Is there about 4V ~ 5V at
the IC152 Pin 4?
Check the “PWR CTL H”
signal from µ-COM
YES
NO
Check the IC152 and replace

3-7
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
No SW_5.3VA
Is the Vcc (5.3V)
supplied to Q158 emiter? Check 5.3VA on SMPS board
YES
YES
NO
Is there about 0V
at R179 and R156?
Check the “STANBY H”
signal from µ-COM
YES
NO
Check Q158 and replace
No SW_FD(+)
Is the Vcc (FD+) supplied
to Q163 collector?
Check D121 on SMPS
board and replace
YES
YES
NO
Is there about 5.3V at
R184 and Q153 collector? Check Q163 and replace
YES
NO
Is the VCC (5.3V)
supplied to Q153 emiter? Check 5.3VA on SMPS board
YES
NO
Is there about 0V
at Q153 base?
Check the “STANBY H”
signal from µ-COM
YES
NO
Check Q153 and replace

3-8 Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
No 1.8V
There is 1,8V at IC155 Pin 2, 4
Is the Vcc (3.3V)
supplied to Pin 3 IC155? Check 3.3V power supply
YES
YES
NO
IC155 defect
NO
No 1.25V
Check the IC154 and replace
Is there about 5.3V at
the IC154 Pin 2? Check 5.3VA on SMPS board
YES
YES
NO
Is there about 4V ~ 5V at
the IC154 Pin 5?
Check the “PWR CTL H”
signal from µ-COM
YES
NO