LG MDD64K User manual

P/NO : AFN73250934 JULY, 2009
DVD Mini Hi-Fi System
SERVICE MANUAL
MODEL : MDD64K (MDS64V)
CAUTION
BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS”
IN THIS MANUAL.
Website http://biz.lgservice.com
Internal Use Only
MODEL : MDD64K (MDS64V)SERVICE MANUAL

1-1
SECTION 1. GENERAL
• SERVICING PRECAUTIONS................................................................................................ 1-2
• ESD PRECAUTIONS ............................................................................................................ 1-4
• SERVICE INFORMATION FOR EEPROM ........................................................................... 1-5
• PROGRAM DOWNLOAD GUIDE ........................................................................................... 1-6
• SPECIFICATIONS................................................................................................................. 1-7
SECTION 2. EXPLODED VIEWS
• CABINET AND MAIN FRAME SECTION.............................................................................. 2-1
• MECHANISM EXPLODED VIEW........................................................................................... 2-3
• SPEAKER EXPLODED VIEW............................................................................................... 2-9
• PACKING ACCESSORY VIEW........................................................................................... 2-10
SECTION 3. ELECTRICAL PART
• TROUBLESHOOTING GUIDE
AUDIO PART TROUBLESHOOTING GUIDE ....................................................................... 3-1
DVD PART TROUBLESHOOTING GUIDE......................................................................... 3-10
• WAVEFORMS OF MAJOR CHECK POINT........................................................................ 3-17
• WIRING DIAGRAM ............................................................................................................. 3-21
• BLOCK DIAGRAMS ............................................................................................................ 3-22
• CIRCUIT DIAGRAMS.......................................................................................................... 3-25
• CIRCUIT VOLTAGE CHART............................................................................................... 3-49
• PRINTED CIRCUIT DIARGAMS ......................................................................................... 3-53
SECTION 4. REPLACEMENT PARTS LIST..................................................................... 4-1
[CONTENTS]

1-2
SERVICING PRECAUTIONS
NOTES REGARDING HANDLING OF THE PICK-UP
1. Notes for transport and storage
1) The pick-up should always be left in its conductive bag until immediately prior to use.
2) The pick-up should never be subjected to external pressure or impact.
2. Repair notes
1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic mate-
rials.
2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure
and impact. If it is subjected to strong pressure or impact, the result may be an operational malfunc-
tion and/or damage to the printed-circuit board.
3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that
reason the adjustment point and installation screws should absolutely never be touched.
4) Laser beams may damage the eyes!
Absolutely never permit laser beams to enter the eyes!
Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged.
5) Cleaning the lens surface
If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as
used for camera lens). The lens is held by a delicate spring. When cleaning the lens surface, there-
fore, a cotton swab should be used, taking care not to distort this.
6) Never attempt to disassemble the pick-up.
Spring by excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab.
(Do not use any other liquid cleaners, because they will damage the lens.) Take care not to use too
much of this alcohol on the swab, and do not allow the alcohol to get inside the pick-up.
Storage in conductive bag Drop impact
NEVER look directly at the laser beam, and don’t allow
contact fingers or other exposed skin.
Magnet
How to hold the pick-up
Conductive Sheet
Cotton swab
Pressure
Pressure
SECTION 1. GENERAL

1-3
NOTES REGARDING COMPACT DISC PLAYER REPAIRS
1. Preparations
1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode). These compo-
nents are sensitive to, and easily affected by, static electricity. If such static electricity is high voltage,
components can be damaged, and for that reason components should be handled with care.
2) The pick-up is composed of many optical components and other high-precision components. Care
must be taken, therefore, to avoid repair or storage where the temperature of humidity is high, where
strong magnetism is present, or where there is excessive dust.
2. Notes for repair
1) Before replacing a component part, first disconnect the power supply lead wire from the unit
2) All equipment, measuring instruments and tools must be grounded.
3) The workbench should be covered with a conductive sheet and grounded.
When removing the laser pick-up from its conductive bag, do not place the pick-up on the bag.
(This is because there is the possibility of damage by static electricity.)
4) To prevent AC leakage, the metal part of the soldering iron should be grounded.
5) Workers should be grounded by an armband (1MΩ)
6) Care should be taken not to permit the laser pick-up to come in contact with clothing, in order to
prevent static electricity changes in the clothing to escape from the armband.
7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin.
Resistor
(1 MΩ)Conductive
Sheet
Resistor
(1 MΩ)
Armband

1-4
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components
commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD 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 electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a
commercially available discharging wrist strap device, which should be removed for potential shock reasons
prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ESD 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 ESD 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 ESD devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD
devices.
6. Do not remove a replacement ESD device from its protective package until immediately before you are
ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive materials).
7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the
protective material to the chassis or circuit assembly into which the device will by installed.
CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER
SAFETY PRECAUTIONS.
8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion
such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate
static electricity sufficient to damage an ESD device).
CAUTION. GRAPHIC SYMBOLS
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS
INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED
“DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF
ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE
SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE
LITERATURE.
SAFETY PRECAUTIONS

1-5
POWER ON
FLD no disc status
Remote control
pause key ->1->4->7->2 in order
FLD ‘OP-0….
Move to appropriate position
and make changes
with Rmc ( ) key
Press STOP key
FLD ‘write ok’
Remote control ‘0’ + Front ‘STOP’
push same timing
FLD ‘E2P CLR’
Completed
NAME
OPT 0
OPT 1
OPT 2
OPT 3
OPT 4
OPT 5
OPT 6
OPT 7
OPT 8
OPT 9
DETECT NEW EEPROM
(OPTION EDIT SCREEN)
HEX
19
0A
A0
DD
00
19
83
20
10
00
SERVICE INFORMATION FOR EEPROM

1-6
Caution) Do not perform any other work such as disconnecting USB device, switching to the Function
and turning off the power while downloading it to the set.
The USB device should be disconnected after completing the download.
• AUDIO USB DOWNLOAD GUIDE
1. When the USB device is inserted on the USB function, is displayed on the screen after a while.
“File : MDT354_YYMMDDX.HEX” * x: version.
2. The message “Upgrade” is displayed while downloading.
3. The power is automatically turned off when downloading is completed.
• DVD USB DOWNLOAD GUIDE
The program file to download should be named as LG_MDS714XXX_YYMMDDX.rom.
- The downloaded file should be modified as LG_MDS714XXX_YYMMDDX.rom.
- After safely storing LG_MDS714XXX_YYMMDDX.rom at the USB device, perform the following steps.
1. When the USB device is inserted at the USB function, the screen is changed into downloading
screen.
2. When downloading is completed, the message “Completed” is displayed at the top left on the screen.
3. Turn on the power, press the SETUP button of the remote controller on the USB FUCTION. When
the SETUP window is displayed on the screen, move down once to select the DISPLAY menu. Go
to the TV Aspect on the right menu, move to “16:9”, enter “1397139” by using the numeric key of the
remote controller, and press the Enter key.
Then, the System Information screen is displayed. If not, retry the steps at the above.
4. When Step 3 is completed, press the Pause key of the remote controller.
5. Disconnect the power cord, and reconnect it after 5 seconds to complete downloading.
6. When the power is turned on, the language selection menu is initially displayed.
After selecting the desired language, press the SELECT/ENTER.
PROGRAM DOWNLOAD GUIDE

1-7
General
Power supply Refer to main label.
Power consumption Refer to main label.
Net Weight 5.4 kg
External dimensions (W x H x D) 274 x 334 x 344 mm
Operating conditions Temperature: 5°C to 35°C,
Operation status: Horizontal
Operating humidity 5% to 85%
Tuner
FM Tuning Range 87.5 ~ 108.0 MHz or 87.50 ~ 108.00 MHz
Intermediate Frequency 128 MHz
AM Tuning Range 522 ~ 1,620 KHz or 520 ~ 1,710 KHz or 522 ~ 1,710 KHz
Intermediate Frequency 45 KHz
Amplifier
Output Power 30 W + 30 W (4 Ω, THD 10 %)
DVD / CD player
Frequency response (audio) 40 ~ 20,000 Hz
Signal-to-noise ratio (audio) More than 75 dB (1 KHz)
Signal-to-noise ratio (video) More than 55 dB (1 KHz)
Dynamic range (audio) More than 80 dB
Video output 1.0 V (p-p), 75 Ω
Component Video output (Y) 1.0 V (p-p), 75 Ω
(Pb)/(Pr) 0.7 V (p-p), 75 Ω
Cassette tape player
F. F / REW Time 120 sec (C-60)
Frequency Response 250 ~ 8000 Hz
Signal to Noise Ratio 43 dB
Channel Separation 50 dB (P/B) / 45 dB (R/P)
Erase Ratio 55 dB (MTT- 5511)
Speakers
MDS64V
Front Speaker
Type 2 Way 2 Speaker
Impedance 4 Ω
Rated Input Power 30 W
Max. Input Power 60 W
Net Dimensions(W x H x D) 220 x 333 x 253 mm
Net Weight 3.1 kg
Designs and specifications are subject to change without pior notice.
SPECIFICATIONS

1-8

T
464
292
J
Q
B
C
A
F
U
O
H
A47
A46
295
300
289
294
463
464
464
464
A00
CABLE1
MAIN
SMPS
C
E
B
D
D
P
P
A
G
O
G
H
I
L
I
A26
CABLE2
K
L
K
E
A41
482
CABLE3
DVD
J
Q
F
251
252
254
255
256
261
260
258
259
464
264
263
250
266
267
265
263
270
271
272
273
268L
269L
269R
268R
262
253
276
253
257
A42
A43
CABLE5
464
464
451
CABLE6
CABLE7
464
464
464
A44
274
277
275
277
T
464
464
464
464
FRONT
293
464
CABLE8
266A
266B
U
NOTES) THE EXCLAMATION POINT WITHIN AN
EQUILATERAL TRIANGLE IS INTENDED
TO ALERT THE SERVICE PERSONNEL
TO THE PRESENCE OF IMPORTANT
SAFETY INFORMATION IN SERVICE
LITERATURE.
SECTION 2. EXPLODED VIEWS
2-1 2-2
1. CABINET AND MAIN FRAME SECTION (MDD64)

2-3 2-4
2. TAPE DECK MECHANISM EXPLODED VIEW
(1) TAPE DECK MECHANISM (A/S & A/S : RIGHT A/S DECK)
BRASS MOTOR PULLEY MAYBE CHANGED
FOR WOW FLUTTER WHEN NECESSARY
RING FW MAYBE ADDED
FOR WOW FLUTTER WHEN NECESSARY
001
002
006
007
008
016 017
018
019
020
003
A00
009
009
A02
A01
011
013
022
025
015
023

2-5 2-6
(2) TAPE DECK MECHANISM (A/S & A/S : LEFT A/S DECK)
RING FW MAYBE ADDED
FOR WOW FLUTTER WHEN NECESSARY
013
011
009
009
003
008
015
022
023
024
016 017
018
019
020
007
A03
A00

151
155
159
170
163
162
177
172
167
166
175 180
137
012
012
A01
A02
012
430
164
173
165
153
156
153A
169A
169B
169C
035
430
430
010
181
A26
3. MECHANISM DECK EXPLODED VIEW (DVM-H1713)
2-7 2-8

2-9
4. SPEAKER EXPLODED VIEW
ᆞFRONT SPEAKER (MDS64V)
653
654
651
653
652
655
A60R
A60L
A61R
A61L
A62R
A62L
656

2-10
5. PACKING ACCESSORY VIEW
801 Instruction Ass'y
808 Battery
824 AM Loop antenna
825 FM wire antenna
900 Remote Control
811 RCA Cable, 1Pin(Black)
803 Packing
804 Bag
802 Caja
803 Packing
801S Song Book
Micro Phone
827
Disc
832

3-1
1. POWER (SMPS)
AUDIO ELECTRICAL TROUBLESHOOTING GUIDE
POWER (SMPS)
NO Replace the fuse
YES
Check the fuse
F901
NO Check BD901, LF901, 902
NO Check short of P9702 line
Check short of
P9701, P9702 line
NO Check short of P9701 line
NO Replace IC901,902
YES
Check
the DC V of C905
if DC V is over
400V
NO
YES
Check the
DC V of C909,C903,C921
If DC V is in 14~19V
and it is steady
Check IC901, 902
YES
YES
Check the
DC V of C981, C945
If DC V is 6.1V
YES
Check the
DC V of C950,C951
If DC V is in
31.68V
YES
OK
SECTION 3. ELECTRICAL PART

3-2
4. MICOM PART CHECK I
2. P-SENS
Check power circuit
troubleshooting
NO
YES
P-SENS
Check
the pin6 of P9702
if DC V is over
5.6V
YES
OK
3. VKK PART CHECK
Check power circuit
troubleshooting
NO
YES
VKK CHECK
Check
the pin3 of P9702
if DC V is over
-28V
YES
OK
OK OK
NO Replace IC101
(KIA7042)
NO
YES
YES
YES YES
Check if IC101 of out-
put voltage is over 4.3V
YES
Check voltage of
IC100(LC87Fxxx) pin4
YES
Refer to SMPS
troubleshooting
MICOM PART
CHECK I
NO
Check P-SENS
(P7904_pin6)
NO
Check both
end voltage of
IC101
(KIA7042)
Check
If input voltage of
IC101 is over
5V
Check the
periphery of IC101
(KIA7042)

3-3
5. MICOM PART CHECK II
NO
YES
YES
NO Refer to SMPS
troubleshooting
YES
Check If IC103_pin8 and
IC100_pin14,40,55,89 are 5V
YES
X101:32.768KHz
X100:9.8304MHz
Check the operation
Check P-SENS
(P7904_pin6)
Check both
end voltage of D101
Check
If output of
D101 is 5V
YES
Check D101
MICOM PART CHECK II
NO Replace D101
YES
OK
YES
OK
6. IC103(S24CS16A01) PART CHECK
YES
YES
YES
YES
pin93:DATA
pin94:CLK
Check MICOM
NO Check MICOM
voltage 5V
CHECK IC100
PIN93,94
NO Replace MICOM
NO Refer to MICOM
troubleshooting
OK OK

3-4
7. FLD DISPLAY CHECK
NO
YES
YES
Refer to SMPS troubleshooting
Check if both end voltage of
F1,F2 are over 3.4V
VKK : over 26V
Check
CN104 pin1, 2, 3 voltage
input
FLD DISPLAY CHECK
YES
YES
YES
FLD light on?
YES
Check
CN304 connection
and power pin24:FL+26,
pin23:FL-22,
pin22:VKK over 26V,
pin19:+5.6V
Check
IC501(ET6315) voltage
pin30 VKK:-26V
pin13, 43:+5V
OK
OK
NO Replace IC501
NO If voltage is not 5V,
check input and output of L502
YES
Check IC501
Check CN304 connection
YES
YES
Check each pin voltage
OK
YES
NO
YES
YES
Check
IC102 --> IC501
data communication
3pin --> 9pin STB
2pin --> 7pin DATA
4pin --> 8pin CLK
OK
NO Replace IC102
NO IC102 : pin2,3,4
check data Input
YES
Check IC102
Pin2 data out
check data input
YES

3-5
8. PWM MODULATION PART CHECK
check P7905 pin9,10
3.3V
PWM MODULATION
PART CHECK
Refer to SMPS
troubleshooting
NO
NO
Check
X601 12.288MHz
operation
check IC604
pin86 CLK input
Check
IC100(LC87Fxx)
pin34:PWM REST
pin86: PWM_DSP_DAT
pin87:PWM_DSP_CLK
output
YES
YES
YES
YES
YES
YES
YES
YES
Check
IC604(PS9830)
pin 23,24,25,26
DATA input,
PWM wave
Check PWM
modulator output
FL:pin75(+),74(-)
FD:pin71(+),70(-)
check other
output
Check IC604(PS9830)
VDD pin voltage (3,10,22,29,
39,47,56,65,72,87,94)
check X601 pin2 :3.3V
OK
Replace X601
NO
YES
Check X601
12.288MHz
OK
Refer to DVD troubleshooting
NO
Check P7403
DVD assy communication
Check each line
resistor output
NO
Check
IC604(PS9830) DATA
input
Replace R671,R670,R665
NO
YES
Check line
resistor output
SDA:R671,SCL:R670
RST:R665
OK
YES
OK
Replace IC604
NO
Check
IC604(PS9830)
YES
OK
NO
NO
YES
NO