LG MDD-K263Q, MDS-K263V Service manual

MODEL : MDD-K263Q (MDS-K263V)

SERVICE MANUAL

P/NO : AFN62795882

KARAOKE MINI Hi-Fi SYSTEM

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL.

MODEL : MDD-K263Q (MDS-K263V)

Website http://biz.lgservice.com

Internal Use Only

SEPTEMBER, 2008

1-1

LGE Internal Use Only

[CONTENTS]

❍ SECTION 1. GENERAL

• SERVICING PRECAUTIONS ................................................................................................ 1-2

• ESD PRECAUTIONS ............................................................................................................ 1-4

• PROGRAM DOWNLOAD GUIDE.......................................................................................... 1-5

• SPECIFICATIONS ................................................................................................................ 1-6

❍ 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

USB PART TROUBLESHOOTING GUIDE .......................................................................... 3-16

• WAVEFORMS OF MAJOR CHECK POINT ........................................................................ 3-17

• WIRING DIAGRAM .............................................................................................................. 3-22

• BLOCK DIAGRAMS ............................................................................................................ 3-23

• CIRCUIT DIAGRAMS .......................................................................................................... 3-25

• INTERNAL BLOCK DIAGRAM OF IC ................................................................................ 3-45

• CIRCUIT VOLTAGE CHART ................................................................................................ 3-59

• PRINTED CIRCUIT DIARGAMS ........................................................................................ 3-65

❍ SECTION 4. REPLACEMENT PARTS LIST ................................................................ 4-1

1-2

Only for training and service purposes

LGE Internal Use Only

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 materials.

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 malfunction 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, therefore, 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

SECTION 1. GENERAL

1-3

LGE Internal Use Only

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 components 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 (1M Ω)

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 Mohm)

Conductive Sheet

Resistor (1 Mohm)

Armband

1-4

Only for training and service purposes

LGE Internal Use Only

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

LGE Internal Use Only

PROGRAM DOWNLOAD GUIDE

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 : MDD263_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 BANK.ROM.

- The downloaded file should be modified as BANK30.ROM.

- After safely storing BANK30.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 Ent er 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. ( * not KARAOKE MODEL )

1-6

Only for training and service purposes

LGE Internal Use Only

SPECIFICATIONS

General

Power supply Refer to main label. Power consumption Refer to main label. Net Weight 6.2 kg External dimensions (W x H x D) 273 x 326 x 380 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 65.0 - 74.0 MHz, 87.5 - 108.0 MHz Intermediate Frequency 10.7 MHz AM Tuning Range 522 - 1,620 kHz or 520 - 1,720 kHz Intermediate Frequency 450 kHz

Amplifier

OUTPUT POWER Front: 130 W + 130 W (4 Ω, THD 10 %)

DVD/ VCD/ CD player

Frequency response (audio) 40 - 20000 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 45 dB (P/ B)/ 45 dB (R/ P) Erase Ratio 50dB (MTT- 5511)

Speakers

MDS-K263V

Front Speaker Type 2Way 3Speaker Impedance 4 Ω Rated Input Power 130 W Max. Input Power 260W Net Dimensions(W x H x D) 212x 413x 301mm Net Weight 5.5 kg

Designs and specifications are subject to change without pior notice.

2-1 2-2

LGE Internal Use Only

• CABINET AND MAIN FRAME SECTION

SECTION 2. EXPLODED VIEWS

252

465

A26

CABLE4

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.

L

K

459

A

KEY2

253

P

A43

A

254

255

465

KEY1

FRONT

256

459

O

MIC

KEY3

261

253

CABLE3

459

H

G

260

251

459

CABLE5

P201

257

A40

J

459

P

255

267

I

A41

DVD

CABLE2

450

266

N

M

465

L

K

N

M

J

A46

D

I

C

MAIN

H

B

O

465

458

465

264

455

465

CABLE6

289

456

D

SMPS

CABLE7

C

A47

263

B

262

273

A00

465

F

CN201

465

E

CABLE1

290

465

291

305

2-3 2-4

Only for training and service purposes

LGE Internal Use Only

MECHANISM EXPLODED VIEW

1. TAPE DECK MECHANISM (A/R & A/S : RIGHT A/R DECK)

BRASS MOTOR PULLEY MAYBE CHANGEDFOR WOW FLUTTER WHEN NECESSARY

RING FW MAYBE ADDEDFOR WOW FLUTTER WHEN NECESSARY

A00

001

002

003

009

011

009

013

A02

015

008

007

006

037

022

023

025

016

017

018

020

A01

019

TAPE DECK MECHANISM EXPLODED VIEW

2. TAPE DECK MECHANISM (A/R & A/S : LEFT A/S DECK)

RING FW MAYBE ADDED FOR WOW FLUTTER WHEN NECESSARY

A00

003

009

011

009

013

A03

015

008

007

022

023

024

016

017

018

020

019

2-5 2-6

LGE Internal Use Only

TAPE DECK MECHANISM EXPLODED VIEW

3. MECHANISM DECK EXPLODED VIEW

2-7 2-8

Only for training and service purposes

LGE Internal Use Only

416

151

159

156 169

422

A26

417

167

416

177

166

164

417

165

440

438

172

175

163

170

419

168

155

162

417

153

173

012A

417

418

169B

169C

430

169A

418

181

A30

430

012A

036

035

180

035A

438

2-9

LGE Internal Use Only

• FRONT SPEAKER (MDS-K263V)

SPEAKER EXPLODED VIEW

A80L

A80R

850

851

853

852

854

A81L

A81R

854

855

856

857

858

860L

860R

861

859

2-10

Only for training and service purposes

LGE Internal Use Only

• PACKING ACCESSORY

VIEW

808 Battery

900 Remote Control

801 Instruction Ass'y

811

Plug Ass'y, 1Way

Antenna Loop

824

827

825 Antenna

Micro Phone

832

DISC

803 Packing

804 Bag

801S

Song Book

803 Packing

802 Box

3-1

LGE Internal Use Only

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER (SMPS)

SECTION 3. ELECTRICAL PART

NO

YES

Replace the fuse.

Check the FUSE

F901.

NO

YES

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.

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

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.

POWER (SMPS)

OK

3-2

Only for training and service purposes

LGE Internal Use Only

2. P-SENS 3. VKK PART CHECK

4. MICOM PART CHECK I

NO

Check power circuit

Troubleshooting.

YES

P-SENS

Check

the PIN6 of P9702

if DC V is over

5.6V

YES

OK

OK OK

NO

Check power circuit

Troubleshooting.

YES

VKK CHECK

Check

the PIN3 of P9702

if DC V is over

-28V.

YES

OK

NO

NO NO

Replace IC101

(KIA7042)

Check if IC101 of output

voltage is over4.3V

YES

YES YES

YES

Check voltage of

IC100(LC87Fxxx)PIN4

YES

Refer to SMPS

troubleshooting.

MICOM PART

HECK I

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)

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

3-3

LGE Internal Use Only

5. MICOM PART CHECK II

6. IC103(S24CS16A01) PART CHECK

NO

YES

Refer to SMPS

troubleshooting.

Check If IC103_PIN8 and

IC100_PIN14,40,55,89 are 5V .

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.

Check D101.

MICOM PART CHECK II

NO

Replace D101.

OK

YES

PIN81:DATA

PIN82:CLK

Check MICOM.

NO

Check MICOM

Voltage 5V.

CHECK IC100

PIN81,82

NO

Replace MICOM.

NO

Refer to micom

troubleshooting.

OK

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

3-4

Only for training and service purposes

LGE Internal Use Only

7. FLD DISPLAY PART CHECK

NO

YES

Refer to SMPS.

NO

Replace P3302.

Check P3302 Connection.

Check if both end voltage of

F1,F2 are over 3.7V.

VKK : Over 28V

YES

FLD light on?

Check

P7904 PIN1,2,3

Voltage input

YES

Check P7302

Connection and Power.

pin29:FL+26,pin28:FL-22,

pin27:Vkk over 28V,

pin24:+5.6V

YES

Check

IC301(PT6324)Voltage

Pin50 VKK:-28V

PIN:9,52:+5V

YES

Check each

PIN voltage.

IC100

Check IC301

Data communication.

Pin pin 27pin 3pin STB 26pin 2pin data 28pin 1pin clk

FLD DISPLAY CHECK

OK

NO

Replace IC301.

NO

Replace IC100.

NO

IF voltage is not 5V.

Check input and output of D303.

IC100 : 27,26,28 PIN Check

DATA INPUT.

26PIN DATA OUT

Check DATA INPUT.

YES

Check IC301.

YES

Check IC100.

OK

YES

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

3-5

LGE Internal Use Only

8. PWM MODULATION PART CHECK

P7905 PIN9,10

3.3V Check

PWM MODULATION

PART CHECK

Refer to SMPS

Troubleshooting

NO

Check

X601 12.288MHz

Operation.

IC604

PIN86 CLK INPUT

Check

IC100(LC87Fxx)

PIN22:PWM REST

PIN79:PWM SDA

PIN80:PWM SCL

OUTPUT

YES

Check

IC604(PS9830)

DATA INPUT PIN23,24,25,26

PWM WAVE

Check.

Check PWM

Modulator output

FL:PIN75(+),74(-) FR:PIN71(+),70(-) OTHER OUTPUT

Check

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

Replace R671,R670,R665

NO

YES

Check LINE

Resistor output

SDA:R671,SCL:R670

RST:R665

Refer to DVD troubleshooting

NO

Check

DVD ASSY Communication

P7403

Check each LINE

Resistor output

NO

Check

IC604(PS9830) DATA

INPUT

OK

YES

OK

Replace IC604.

NO

Check

IC604(PS9830)

YES

OK

NO

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

3-6

Only for training and service purposes

LGE Internal Use Only

9. PWM MODULATION PART CHECK

YES

NO

Refer to SMPS Troubleshooting.

P7905 PIN3:+12v

PIN13,14,15:32V

YES

NO

Check each line resistor output voltage.

Check each

IC700 PIN1,22,23,44:+12V

INPUT

YES

NO

Replace the coil.

Check output

line coil.

POWER AMP PART CHECK

OK

Check each IC700,701,702,703

PIN27,26,32,35,40,41 INPUT VOLTAGE

YES

Check PWM Modulator input

each PIN6,8,16,18.

YES

POWER IC700

PIN28,31,36,39 output.

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

3-7

LGE Internal Use Only

10. AUX FUNCTION PART CHECK

OK

Check

IC200 (BU4052)

PIN3,13 each function

output.

Check

IC200 (BU4052)

PIN7:-12V

PIN:16:+12V

Check IC801

(MC4580)

PIN1,7 output.

Check

IC201 (CS5345)

PIN26,27 INPUT.

Check

IC201 (CS5345)

PIN41 data output.

FUNCTION CHECK

Each function

(tuner/tape/portable)

output to IC200(BU4052)

input : L/R_CH.

Check P7501

PIN6(L-CH),PIN8(R-CH).

Each function

output line Check.

Check

IC801 (MC4580)

PIN:-12V

PIN:8:+12V

Check ic201

PIN46:+3.3V

PIN14:+5V

Check ic201

PIN1:SDA PIN2:SCL PIN6:RST

Refer to SMPS.

Check CN202 Connection.

IC501(ES8390)

PIN55 INPUT DATA.

IC501(ES8390)

DADATA0 OUTPUT.

Check P7905 connection

After replace IC200.

Check CN202 PIN4,5:+5V

PIN11,12: +3.3V

Check CN206

PIN8:SDA,PIN9:SCL,PIN10:RST

Replace IC201.

YES

NO

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

3-8

Only for training and service purposes

LGE Internal Use Only

11. TUNER/TAPE/PORTABLE FUNCTION PART CHECK

NO

YES

Refer to SMPS troubleshooting.

Check A DECK head input IC201_PIN32, 39 and B DECK head input IC201_PIN34, 37.

Check IC210

(HA12237)_PIN16

12V in put.

Check

IC201_ PIN5,

26 signal output.

YES

Check

IC201_PIN14

mute operation.

YES

Check IC201.

Check A/B

DECK head input.

TAPE PLAY PART CHECK

NO

Replace head wire and tape

DECK mechanism.

NO

Replace IC201.

OK

YES

OK

NO

Check IC202_PIN10 "HIGH"

YES

Check IC202.

NO

Replace IC202.

YES

OK

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

3-9

LGE Internal Use Only

12. TAPE PLAY PART CHECK

NO

Refer to PWM modulation

troubleshooting.

Check

IC604(PS9829)

_PIN49, 52 PWM

output.

Check IC201_

PIN10, 21 output.

Check IC100_ PIN23 "HIGH"

TAPE REC PART CHECK

NO

Replace IC201.

Replace IC202.

Check IC201_PIN7, 24

record input.

YES

OK

NO

Check L203_PIN2, 3

oscillation

Check Q205(D1304)_

base "HIGH"

NO

Check IC202_PIN4 "HIGH".

YES

OK

YES

Check P2203_PIN5, 3inputand

PIN8 erase input.

YES

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE