LG XC62, XCS62F Service manual

MICRO Hi-Fi SYSTEM

SERVICE MANUAL

MODEL : XC62 (XCS62F)

CAUTION

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

.

MODEL : XC62 (XCS62F)

SERVICE MANUAL

P/NO : AFN33894992 APRIL, 2007

http://biz.lgservice.com

CONTENTS

SECTION 1
GENERAL

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

• NOTES REGARDING HANDLING OF THE PICK-UP

•

NOTES REGARDING COMPACT DISC PLAYER REPAIRS

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

LOCATION OF USERS CONTROLS .........................1-5

SPECIFICATIONS ........................................................1-7

SECTION 2
EXPLODED VIEWS

CABINET EXPLODED VIEW......................................2-1

TAPE DECK MECHANISM (SINGLE DECK)

EXPLODED VIEW ........................................................2-3

CD MECHANISM EXPLODED VIEW.........................2-5

SPEAKER EXPLODED VIEW ....................................2-7

MODEL : XCS62F ....................................................2-7

PACKING ACCESSORY VIEW...................................2-9

SECTION 3
AUDIO PART ELECTRICAL

AUDIO ELECTRICAL

TROUBLESHOOTING GUIDE....................................3-1

1. POWER (SMPS) ................................................3-1

2. MICOM PART CHECK I ....................................3-4

3. MICOM PART CHECK II ...................................3-5

4. IC103(KS4CD21CS) CHECK............................3-6

5. FLD DISPLAY CHECK ......................................3-7

6. PWM MODULATION PART CHECK................3-8

7. POWER AMP PART CHECK............................3-9

8. AUX FUNCTION CHECK................................3-10

9. TUNER FUNCTION CHECK...........................3-11

10. TAPE FUNCTION CHECK ..............................3-12

11. TAPE PLAY PART CHECK..............................3-13

12. TAPE REC PART CHECK...............................3-14

13. PORTABLE IN FUNCTION CHECK...............3-15

INTERNAL BLOCK DIAGRAM OF ICs...................3-15

1. AK5358..............................................................3-16

2. BU4052 .............................................................3-16

3. HA12237F.........................................................3-17

4. LC78692NW .....................................................3-18

5. PS9829B...........................................................3-18

6. PT6324..............................................................3-19

7. STR-W6253......................................................3-19

8. TAS5142 ...........................................................3-20

9. U1739EJ2V1UD00/KF2_E ..............................3-21

10. UTC MC4580....................................................3-22

WIRING DIAGRAM ....................................................3-24

BLOCK DIAGRAM.....................................................3-26

1. SMPS BLOCK DIAGRAM...............................3-26

2. MAIN & FRONT BLOCK DIAGRAM ..............3-28

SCHEMATIC DIAGRAMS .........................................3-30

1. SMPS SCHEMATIC DIAGRAM.......................3-30

2. MAIN SCHEMATIC DIAGRAM ........................3-32

3. AMP SCHEMATIC DIAGRAM..........................3-34

4. DECK SCHEMATIC DIAGRAM .......................3-36

5. FRONT SCHEMATIC DIAGRAM.....................3-38

PRINTED CIRCUIT BOARD DIAGRAMS ...............3-40

1. MAIN P.C.BOARD ............................................3-40

2. SMPS P.C.BOARD ..........................................3-44

3. FRONT P.C.BOARD ........................................3-46

SECTION 4
CD PART ELECTRICAL

CD ELECTRICAL TROUBLESHOOTING GUIDE....4-1

1. CD PART TROUBLESHOOTING.....................4-1

2. USB PART TROUBLESHOOTING...................4-9

WAVEFORMS OF MAJOR CHECK POINT............4-10

1. MICOM INTERFACE WAVEFORM.................4-10

2. SLED DRIVE AND MOTOR WAVEFORM......4-11

3. FOCUS DRIVE AND MOTOR

WAVEFORM ......................................................4-11

4. SPINDLE DRIVE AND MOTOR

WAVEFORM......................................................4-12

5. TRACK DRIVE AND MOTOR

WAVEFORM......................................................4-12

6. RF, FOCUS AND TRACKING

ERROR WAVEFORM .......................................4-12

SCHEMATIC DIAGRAMS .........................................4-13

1. CD SCHEMATIC DIAGRAM ...........................4-13

2. USB SCHEMATIC DIAGRAM.........................4-15

PRINTED CIRCUIT BOARD DIAGRAM..................4-17

CD P.C.BOARD ....................................................4-17

SECTION 5
REPLACEMENT PARTS LIST

........5-1

1-1

SECTION 1 GENERAL

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.

1-2

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 (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.

CLEARING MALFUNCTION

You can reset your unit to initial status if malfunction occur(button malfunction, display, etc.).
Using a pointed good conductor(such as driver), simply short the RESET jump wire on the inside of
the volume knob for more than 3 seconds.
If you reset your unit, you must reenter all its settings(stations, clock, timer)

NOTE: 1. To operate the RESET jump wire, pull the volume rotary knob and release it.

2. If you wish to operate the RESET jump wire, it is necessary to unplug the power cord.

1-3

ESD PRECAUTIONS

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 know 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 ARROWHEAD 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 INTENED TO
ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY
INFORMATION IN SERVICE LITERATURE.

1-4

LOCATION OF USERS CONTROLS

FRONT / BACK PANEL

1

2

3

4
5

6

1. DISPLAY WINDOW

2. (POWER)

3. PLAY(PAUSE)

4. • (CD SKIP/SEARCH)

(FAST REWIND PLAY)

• TUNE.-

5. • PORT.IN jack

• (Headphone jack) : ø3.5mm

6. • FUNCTION

(FM, AM, CD, USB, AUX, PORTABLE, TAPE)

• XDSS plus

• PLAY MODE/ST./MONO

• CD SYNC

• CD OPEN (DEMO)

13

12

11
10
9

8

7

14

17

15

16

7. PUSH EJECT position

8. (USB connector)

9. • (CD SKIP/SEARCH)
(FAST FORWARD PLAY)

• TUNE.+

10.VOLUME CONTROL KNOB

11. STO P

12.• TIMER

• CLOCK

• SET (RDS - OPTIONAL)

13.DISC TRAY

14.AM/FM ANTENNA TERMINAL

15.AUX IN (AUXILIARY INPUT) connector

16.POWER IN (POWER CORD)

17.SPEAKER TERMINAL

1-5

REMOTE CONTROL

POWER

DIMMER
MUTE

PRESET/FOLDER( )

/

SLEEP

CD FUNCTION

(PLAY/PAUSE) •

(CD STOP) •

(CD SKIP/SEARCH) •

TUN.-/+ •

REPEAT •

D.SKIP

XTS Pro •

XDSS plus •

EQ master •

RDS (Radio Data System) FUNCTION

RDS : OPTIONAL •

PTY : OPTIONAL •

PTY SEARCH : OPTIONAL •

• USB

• FUNCTION

VOLUME ( )

/

CLOCK

PROGRAM/MEMO

TAPE FUNCTION

• (BACKWARD PLAY)

• (FORWARD PLAY)

• (FAST REWIND PLAY)

• (FAST FORWARD PLAY)

• / (RECORD/RECORD PAUSE)

• (TAPE STOP)

RANDOM

MP3 Info
(MP3/WMA file information display)

NUMERIC

1-6

SPECIFICATIONS

• GENERAL

Power supply Refer to the back panel of the unit.
Power consumption Refer to the back panel of the unit.
Net Weight 3.4kg
External dimensions (WxHxD) 170 x 243 x 282mm

• TUNER
FM Tuning Range 87.5 ~ 108.0MHz or 65 ~ 74MHz, 87.5 ~ 108.0MHz

Intermediate Frequency 10.7MHz
Signal to Noise Ratio 60/55dB (MONO/STEREO)
Frequency Response 50 ~ 10000Hz

AM Tuning Range 522 ~ 1620kHz or 520 ~ 1720kHz

Intermediate Frequency 450kHz
Signal to Noise Ratio 30dB
Frequency Response 140 ~ 1800Hz

• AMPLIFIER

Output Power 30W + 30W
T.H.D 0.5%
Frequency Response 40 ~ 20000Hz
Signal-to-noise ratio 75dB

• CD

Frequency response 40 ~ 20000Hz
Signal-to-noise ratio 75dB
Dynamic range 75dB

• CASSETTE TAPE PLAYER

Tape Speed 3000 ± 3% (MTT-111. NORMAL-SPEED)
Wow Flutter 0.25% (MTT-111, JIS-WTD)
F.F/REW Time 120sec (C-60)
Frequency Response 250 ~ 8000Hz
Signal to Noise Ratio 43dB
Channel Separation 45dB (P/B) / 45dB (R/P)
Erase Ratio 50dB (MTT-5511)

• SPEAKERS

Type 1Way 1Speaker
Impedance 4Ω
Frequency Response 75 ~ 17000Hz
Sound Pressure Level 83dB/W (1m)
Rated Input Power 30W
Max. Input Power 60W
Net Dimensions (WxHxD) 144 x 243 x 171mm
Net Weight (1EA) 1.47kg

1-7

MEMO

1-8

A

C

D

H

I

A

B

K

E

J

F

L

B

C

E

G

L

D

F

H

I

J

K

G

454

A26

A46

264

263

266

A43

250

254

252

253

255

259

454

A47

CN2

CN1

305

454

454

454

A00

267

290

256

A52

CD

SMPS

FRONT

MAIN

CABLE3

CABLE2

CABLE1

CN201

454

290

454

454

454

SECTION 2 EXPLODED VIEWS

257

258

CABINET EXPLODED VIEW

TAPE DECK MECHANISM (SINGLE DECK) EXPLODED VIEW

A00

009

003

001

007

037

015

006

017

020

019

022

018

A01

023

025

011

A02

009

CD MECHANISM (CDM-330) EXPLODED VIEW

A26

018

439

014

013

017

A02

020

001

A01

002

003

015

026

431

016

A03

432

012

019

012A

010

036

012A

432

012

037

SPEAKER EXPLODED VIEW

MODEL : XCS62F

850L

851

A80

852

A80L

853L

854

WIRE80

A81

853R

A80R

852

850R

854

851

WIRE80

PACKING ACCESSORY VIEW

808 Battery

900 Remote Control

801 Instruction Ass'y

803 Packing

804 Bag

824 Antenna Loop (AM)

825 Antenna (FM)

803 Packing

802 Box

2-9

SECTION 3 AUDIO PART ELECTRICAL

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER (SMPS)

No .5.6VA

YES

Is the F101 normal? Replace the F101 (Use the same fuse)

YES

Is the BD101 normal? Replace the BD101

YES

Is the TH101 normal? Replace the R101

YES

NO

NO

NO

Is Vcc (9V - 18V)

supplied to IC101 Pin2?

YES

IS the D959 normal? Replace the D959

YES

Is there about 2.5V at the

IC103 Pin1?

YES

Is the IC102 normal? Replace the IC102

YES

Is the D947 normal? Replace the D947

YES

Is the D949 normal? Replace the D949

YES

Is the D940 normal? Replace the D940

NO

NO

NO

NO

NO

NO

NO

Is the D102 normal?

NO

Check or Replace the D102

Replace the IC103

YES

Is the D943 normal? Replace the D943

YES

Is the D941 normal? Replace the D941

YES

NO

NO

Power line of main PCB is short

3-1

No 5.0V

YES

Is the Vcc(5.6V)

supplied to IC957 pin1?

YES

Is the IC957 pin4 “H”?

YES

Check or Replace the IC957

No 3.3V

YES

Is the Vcc(4.2V)

supplied to IC955 pin1?

YES

Is the IC955 pin4 “H”?

NO

NO

NO

NO

Check or Replace the D959

Check the CD CTL “H”

signal from µ-com

Check or Replace the D943

Check the P CTL “H”

signal from µ-com

YES

Check or Replace the IC955

No 12V

YES

Is the Vcc(13.5V)

supplied to IC947 pin1?

YES

Is the IC947 pin4 “H”?

YES

Check or Replace the IC947

NO

NO

Check or Replace the D940

Check the P CTL “H”

signal from µ-com

3-2

No -12V

YES

Is the voltage 0f

C932 -13V

YES

Is the IC155 pin2

12V?

YES

Check or Replace the Q942

No VF+

YES

Is the ZD950

Normal?

YES

Replace the R993 or Q950, Q943

NO

NO

NO

Check or Replace the D970

Check the PWR CTL

“H” signal from µ-com

Replace the ZD950

3-3

2. MICOM PART CHECK I

MICOM part check I

YES

Check P-SENS

(P7904)_PIN6.

YES

Check both

end voltage of IC101

(KIA7042).

YES

Check voltage of IC100

78KO/KF2_PIN1.

YES

OK OK

NO

SMPS troubleshooting.

NO

Check if IC101(KIA7042) of

output voltage is over 4.3V.

Refer to

Check

if input voltage of

IC101(KIA7042) is

over 5V.

YES

YES

NO

Check the

periphery of IC101

(KIA7042).

YES

NO

Replace IC101

(KIA7042).

3-4

3. MICOM PART CHECK II

MICOM part check II

YES

voltage of P7904_PIN5

Check if

is 5.6V.

YES

Check

both end voltage of

D101

YES

Check

Q101_ emitter/collector

5V.

YES

NO

NO

NO NO

Refer to

SMPS troubleshooting.

Check if output of

D101(RL104) is 5V.

YES

Check D101.

YES

OK

Check Q102_base

0.6V HIGH.

YES

NO

Replace D101.

Check if output of IC101

(KIA7042) is over 4.3V.

YES

Check if IC103_PIN8 and

IC100_PIN19, 20, 59 are 5V.

YES

X101 : 32.768kHz

X100 : 9.8304MHz

Check the operation.

YES

OK

Q102_collector 0.6V LOW.

YES

Check Q102.

YES

OK

3-5

NO

Check IC101.

YES

OK

Replace Q102.

NO

Replace IC101.

4. IC103(KS4CD21CS) CHECK

Check

IC100(78KOKF2)_

PIN 22, 24

YES

PIN22

DATA PIN24 CLK

YES

OK

Check micom

voltage 5V.

YES

Check micom.

YES

OK

NONO

NO

Refer to

micom troubleshooting

Replace micom.

3-6

5. FLD DISPLAY CHECK

FLD display check

YES

P7904_PIN1, 2, 3 voltage

Check

input.

YES

Check if both end votage

of F1, F2 are over 3.7V.

VKK : over 26V.

YES

Check WF31

connection and power.

Pin1 : FL-22 Pin2 : FL+26

Pin3 : VKK- over

26V.

YES

Check

IC301(PT6324) voltage.

Pin50 VKK : -26V

PIN9.52 : +5V

NO

NO

NO

Refer to SMPS

Check WF31 connection.

YES

Check each

PIN voltage.

YES

OK

If voltage is not 5V,

check input and output

of D301(1SR35).

YES

NO

Replace WF31.

YES

IC100 - >

Check IC301

DATA communication.

PIN PIN
75PIN - > 3PIN STB
76PIN - > 2PIN D
78PIN - > 1PIN

CLK

YES

YES

NO

Check IC301.

YES

OK

IC100

75 PIN - > STB

77 PIN - > 4PIN DI

78 PIN - > 1PIN CLK

Check data output.

YES

76 PIN - > DO - - >

Check DATA in Check IC100.

YES

Check IC100.

YES

OKOK

3-7

NO

NO

Replace IC301.

Replace IC100FLD light on?