LG LM-U360, LMS-U360, LM-U365, LMS-U365 Service Manual

3CD CHANGER MINI Hi-Fi SYSTEM

SERVICE MANUAL

MODEL : LM-U360/LMS-U360, LM-U365/LMS-U365SERVICE MANUAL

P/NO : AFN31223617 JULY,2006

MODEL : LM-U360/LMS-U360,

LM-U365/LMS-U365

[CONTENTS]

❍ SECTION 1. GENERAL

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

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

• SPECIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5

❍ SECTION 2. ELECTRICAL

• ELECTRICAL TROUBLESHOOTING GUIDE(AUDIO PART) . . . . . . . . . . . . . . . . . . . . . . . . 2-1

• INTERNAL BLOCK DIAGRAM of ICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13

• ELECTRICAL TROUBLESHOOTIHG GUIDE & WAVEFORM(CD PART) . . . . . . . . . . . . . . 2-22

• WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-36

• BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-38

• SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-40

• PRINTED CIRCUIT DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-54

❍ SECTION 3. EXPLODED VIEWS

• CABINET AND MAIN FRAME SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1

• TAPE DECK MECHANISM (A/R & A/S : RIGHT A/R DECK) . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

• TAPE DECK MECHANISM (A/R & A/S : LEFT A/S DECK) . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5

• CD MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7

• SPEAKER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

❍ SECTION 4. REPLACEMENT PARTS LIST

• REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1

- 1-1 -

- 1-2 -

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.

Storage in conductive bag

Drop impact

NEVER look directly at the laser beam, and don’t let contact fingers or other exposed skin.

Magnet

How to hold the pick-up

Conductive Sheet

Cotton swab

Pressure

- 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 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.

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.

Resistor (1 Mohm)

Conductive Sheet

Resistor (1 Mohm)

Armband

RESET jump wire

VOLUME

VOLUME KNOB

DOWN

- 1-4 -

❏ 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 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 sur-

face 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.

- 1-5 -

❏ SPECIFICATIONS

[GENERAL]

Power supply Refer to the back panel of the unit. Power consumption Refer to the back panel of the unit. Net Weight 6.2 kg External dimensions (W x H x D) 273 x 321x 359 mm

[CD]

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

[TUNER] FM

Tuning Range 87.5 - 108.0 MHz Intermediate Frequency 10.7 MHz Signal to Noise Ratio 60/55 dB Frequency Response 50 - 10000 Hz

AM [MW]

Tuning Range 522 - 1620 kHz or 520 - 1720 kHz

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

[AMP]MPLIFIER(LH-W96’s)

Output Power 100W +100W+150W [LM-U1560+LMS-U1560W(SUB WOOFER)]

100W+100W [LM-U1060] 50W +50W [LM-U560]

30W + 30W [LM-U360] T.H.D 0.5% Frequency Response 40 - 20000 Hz Signal-to-noise ratio 75 dB

[TAPE]

Tape Speed 4.75cm/sec 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 50dB(P/B)/45dB(R/P) Erase Ratio 55dB (MTT-5513)

[SPEAKERS]

MODEL LMS-U1560 LMS-U1560W LMS-U560 LMS-U360

LMS-U1060 (SUB WOOFER) Type 2way 2speaker 1way 1speaker 2way 2speaker 2way 2speaker Impedance 4Ω 3Ω 4Ω 4Ω Frequency Response 50-20000Hz 50-15000Hz 55-20000Hz 55-20000Hz Sound Pressure Level 85dB/W (1m) 84dB/W (1m) 86dB/W (1m) 86dB/W (1m) Rated Input Power 100W 180W 50W 30W Max. Input Power 200W 360W 100W 60W Net Dimensions (W x H x D)

229X224X286mm 273x325x384mm 229X224X286mm 229X224X286mm Net Weight 3.8kg 6kg 3.9kg 3.8kg

- 1-6 -

- 2-1 -

SECTION 2. ELECTRICAL

❏

ELECTRICAL TROUBLESHOOTING GUIDE(AUDIO PART)

P7904 6PIN P-SENS check

Refer to SMPS

Troubleshooting

Check if IC101 KIA7042 input is over 5V

Check if IC101 KIA7042

input is over 4.3V

IC101 KIA7042 relevant parts check

relevant parts

replacement

normal

IC101 KIA7042?

IC100 78KO/KF2 1 PIN Power Check

normal

YES

NO NO

YES

■ MICOM PART CHECK I

- 2-2 -

■ MICOM PART CHECK II

Q102 BASE PIN

0.6V HIGH check

Q102 COLLECTOR

0.6V LOW check

Check if IC101 KIA7042 output power is over 4.3V

relevant parts check

relevant parts

replacement

normal

relevant parts

replacement

relevant parts check

normal

IC 103 8PIN IC 100 19,20,59 PIN 5V check

X101:32.768KHz X100:9.8304MHz operation status check

normal

P7904 5PIN 5.6V check

Refer to SMPS

Troubleshooting

Output 5V operation check D101 1SR35

relevant parts check

normal

relevant parts

replacement

D101 1SR35 both terminal power check

Q101 EMITTER 5V check and COLLECTO

YES

- 2-3 -

■ IC103 KS4CD21CS CHECK

IC100 78KOKF2 22,24

PIN Check

■ FLD DISPLAY CHECK

22 PIN DATA MICOM power 5V check

Refer to MICOM

Troubleshooting

relevant parts

replacement

relevant parts check

normal

Refer to SMPS

Troubleshooting

P7302 assembly check

Each PIN power check

normal

relevant parts

replacement

normal

P7904 1,2,3 power check

F1+, F2 both terminal: 5V and above VKK: power is over 26V

P7302 connection status check and power check F+,F2- both termainal: 5V or above VKK:26V or above power check

IC301 PT6324 Power check 50 PIN VKK:-26V 9, 51 PIN +5V

YES

- 2-4 -

IC100 ➞ IC301 DATA Communication check PIN PIN (ST8)75 PIN ➞ 3PIN(STB) (DO) 76 PIN ➞ 2PIN(DO) (DI) 77 PIN ➞ 4PIN(DI) (CLK)78 PIN ➞ 1PIN(CLK)

If 5V defective D321 SR35 input and output power check

relevant parts check

76 PIN ➞ DATA input check

relevant parts check

relevant parts

replacement

normal

relevant parts

replacement

normal

FLT light on

normal

IC100 (STB)75 PIN ➞ (STB) (DO) 77 PIN ➞ 4PIN(DO) (CLK) 78 PIN ➞ 1PIN(CLK) Data output check

YES

- 2-5 -

■ PWM ALTERATION PART CHECK

P7905 9PIN 3.3V check

X601 12.288MHz operation check

IC604 PS9829 86 PIN CLK input check

IC100 78KOKF2 21 ➞ PWM_CLK 22 ➞ PWM_DATA 23 ➞ PWM_REST output check

IC604 PS9829 DATA input check 78 PIN ➞ DATA 79 PIN ➞ CLK 96 PIN ➞ REST

PWM MODULATOR output check FL:75(+)74(-)FR:71(+)70(-) SW:68(+)67(-)

normal

IC604 PS9829 VDD PIN Power check (3.10.22.29.39.47.56.65.72.

87. 94)

Refer to SMPS

Troubleshooting

relevant parts check X604

12.288MHz

normal

R668(470Ω) output check

normal

LINE resistance check DATA:R671 CLK:R670 RST:R665

normal

CD ASS`Y PS9829 communication status check(P7403)

IC604 PS9829 DATA input check

normal

IC604 PS9829 parts check

relevant parts

replacement

relevant parts

replacement

relevant parts

replacement

Refer to CD

Troubleshooting

Check each line

resistance check

YES

- 2-6 -

■ POWER AMP PART CHECK

P7905 3 PIN+12 13.14.15 PIN [ LM-U1560 : 32V/LM-U1060 : 32V/LM-U560 : 22V/LM-U360 : 16V ]

Each IC700,701 34, 29, 26, 21 PIN input power check

Each IC700, 701 1, 36.17, 18, 19 PIN +12V input power check

PWM MODULATOR input power check Each IC

4.6.14.16 PIN

POWER IC 700.701.702.703

34.29.27.20 PIN output check

Output LINE COIL check

normal

Refer to SMPS

Troubleshooting

Each LINE resistance output power check IC700:R702, 701, 726, 727,

724

IC701:R730, 729, 750 ,753,

752(Only LM-U1560)

relevant parts

replacement

YES

- 2-7 -

■ AUX FUNCTION

Check whether JK800 contacts or not

IC200 (BU4052)4,11PI N input waveform check

IC200 (BU4052)3,13PIN output waveform check

IC801 (MC4580) 3, 5 PIN input waveform check

IC801(MC4580) Pins 1, 7 output check

IC603(CS5340) Pins10, 12 input check

normal

IC200 (BU4052)16PINVDD, 8PIN VSS power check

µ-COM (IC100) 3, 6PIN Communication check

Refer to SMPS

Troubleshooting

IC603 Pins2, 7, 8 check

relevant parts

replacement

IC801 (MC4580)4PIN VSS,8PIN VDD power check

relevant parts

replacement

IC603 Pin4 SDout check

Relevant Part repplacement

YES

- 2-8 -

■ TUNER FUNCTION CHECK

Tuner module (TUN800)

operation check

■ TAPE FUNCTION CHECK

TUNER MODUEL power check (2PIN 9Vcheck)

IC200 (BU4052)16PIN-

VDD,8PIN VSS power check

IC801(MC4580)4PIN VSS,8PIN VDD power check

IC200 (BU4052)16PINVDD,8PIN VSS power check

IC200(BU4052)1, 12PIN input waveform check

IC200 (BU4052)3,13PIN output waveform check IC601(BU4052)2,15PIN input waveform check

IC801 (MC4580)2,6PIN input waveform check.

TAPE PCB ASS`Y

IC801 (MC4580)2,6PIN input check

IC200(BU4052)2,1 5PIN input waveform check

IC200 (BU4052)3,13PIN output check IC601(BU4052) 2,15PIN input waveform check

YES

IC801(MC4580) Pins 1, 7 input check

YES

IC603(CS95340) Pins10, 12 input check

YES

IC801(MC4580) Pins 1, 7 input check

IC603(CS95340) Pins10, 12 input check

YES

NO YES

relevant parts replacement

YES

relevant parts replacement

YES

relevant parts replacement

IC200 (BU4052)16PINVDD,8PIN VSS power check

NO YES

relevant parts replacement

- 2-9 -

■ TAPE PLAY PART CHECK

P2707:4 PIN ➞ 12V

IC201 (HA12237)16 PIN 12V input waveform check

IC201:5.26 PIN Signal Output check

IC20114 PIN MUTE

operation check

normal

Refer to SMPS

Troubleshooting

DECK HEAD input check

DECK HEAD input IC201

32.39 PIN check

HEAD WIRE or Mecha replacement

relevant parts replacement

relevant parts check

normal

IC202 10 PIN HIGH operation

check

relevant parts check

normal

YES

- 2-10 -

■ TAPE REC PART CHECK

IC604 PS9829 #49,#52 PWM output check

Refer to PWM modulation part

Q601 Collector waveform check

Board to Board cantact check

IC203 8 PIN +12V check

relevant parts check

normal

Q205(D1304) BASE HIGH check

IC202 4 PIN HIGH operation check

Refer to SMPS

Troubleshooting

relevant parts

replacement

relevant parts

replacement

normal

P7207 #2.#4 output check

P2707 #5.#7 input check

IC203 MC4580 #1,#7 check

IC201 7.24 PIN REC input check

IC201 10.21 PIN output check

L203 2.3 PIN oscillation check

P2203 5.3 PIN input check 8 PIN ERASE input check

normal

YES

- 2-11 -

■ SMPS POWER CIRCUIT

Check the fuse F901

Check the DC V of C905. If DC V is over 400V

Check the DC V Of C981,C945. If DC V is 6.1V

Chcek the DC VOf C950,C951 If DC V is in 35V,-35V

Chcek the DC V Of C909, C903,C921 If DC V is in 14~19V and it is steady.

Replace the fuse

Check BD901, LF901,902

Check IC901 ,902 Replace IC 901,902

Check short of P9702 line

Check short of P9701 line

Check short of P9701,P9702

line

*MAIN PART

YES

NO NO

- 2-12 -

Check the PIN6 OF P9702 If DC V is over 5.6V

Check power circuit Trouble shooting

*P-SENS PART (OPTIONAL PART)

Check the PIN3 OF P9702 If DC V is over -28V ±2

Check power circuit Trouble shooting

*VKK PART

YES

- 2-13 -

❏ INTERNAL BLOCK DIAGRAM of ICs

• UTC MC4580

PIN CONFIGURATION

TEST CIRCUIT

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