LG MDT352 Service Manual

MODEL : MDT352(MDS352V, MDS352W)

SERVICE MANUAL

MINI HOME THEATER

SERVICE MANUAL

CAUTION

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

MODEL : MDT352(MDS352V, MDS352W)

Website http://biz.lgservice.com

Internal Use Only

P/NO : AFN62795834 MAY, 2008

1-1

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 AND MAIN FRAME SECTION..................2-1

TAPE DECK MECHANISM EXPLODED VIEW ........2-3

1. TAPE DECK MECHANISM

(A/R & A/S : RIGHT A/R DECK)........................2-3

2. TAPE DECK MECHANISM

(A/R & A/S : LEFT A/S DECK) ..........................2-5

DVD MECHANISM EXPLODED VIEW ......................2-7

SPEAKER EXPLODED VIEW ....................................2-9

1. MODEL : MDS352V (FRONT SPEAKERS).......2-9

2. MODEL : MDS352W (SUBWOOFER) .............2-11

PACKING ACCESSORY VIEW.................................2-13

SECTION 3 AUDIO PART ELECTRICAL

AUDIO ELECTRICAL

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

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

2. P-SENS...............................................................3-2

3. VKK CHECK.......................................................3-2

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

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

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

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

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

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

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

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

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

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

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

INTERNAL BLOCK DIAGRAM OF ICs...................3-13

1. ES6838 ..............................................................3-13

2. HA12237F..........................................................3-14

3. PS9829B............................................................3-15

4. PT6324...............................................................3-15

5. STR-S6757IF1905 ............................................3-16

6. TAS5142.............................................................3-17

7. U1739EJ2V1UD00/KF2_E ...............................3-18

WIRING DIAGRAM ....................................................3-20

BLOCK DIAGRAM.....................................................3-22

1. SMPS BLOCK DIAGRAM...............................3-22

2. MAIN & FRONT BLOCK DIAGRAM ..............3-24

SCHEMATIC DIAGRAMS .........................................3-26

1. SMPS SCHEMATIC DIAGRAM .......................3-26

2. MAIN SCHEMATIC DIAGRAM ........................3-28

3. AMP SCHEMATIC DIAGRAM..........................3-30

4. DECK SCHEMATIC DIAGRAM .......................3-32

5. FRONT SCHEMATIC DIAGRAM.....................3-34

PRINTED CIRCUIT DIAGRAMS...............................3-36

1. MAIN P.C.BOARD............................................3-36

2. SMPS P.C.BOARD ..........................................3-40

3. FRONT P.C.BOARD ........................................3-42

SECTION 4 DVD PART ELECTRICAL

DVD ELECTRICAL

TROUBLESHOOTING GUIDE....................................4-1

1. POWER CHECK GUIDE...................................4-1

2. TEST & DEBUG FLOW.....................................4-2

3. USB PART ..........................................................4-7

WAVEFORMS ...............................................................4-8

1. WHEN POWER ON,

RESET & DATA ETC WAVEFORM ...................4-8

2.

OPEN / CLOSE WAVEFORM AT POWER ON

.......4-9

3.

STARTING ACTION WAVEFORM IN MD DEVICE

......4-9

4. FOCUS WAVEFORM (AT CD).........................4-10

5. FOCUS WAVEFORM (AT DVD) ......................4-10

6.

AT POWER ON, SPINDLE SIGNAL AT MD DECK

........4-11

7.

AT FIRST ACTION, FOCUS SIGNAL A, B, C, D

....4-11

8. TRACKING SIGNAL..........................................4-12

9. RF WAVEFORM ................................................4-12

10. DISK TYPE JUGEMENT WAVEFORM...........4-13

SCHEMATIC DIAGRAMS .........................................4-15

1. MPEG SCHEMATIC DIAGRAM .....................4-15

2. SERVO SCHEMATIC DIAGRAM ...................4-17

3. INTERFACE SCHEMATIC DIAGRAM ...........4-19

PRINTED CIRCUIT DIAGRAM .................................4-21

DVD P.C.BOARD .................................................4-21

SECTION 5 REPLACEMENT PARTS LIST

........5-1

LGE Internal Use Only

1-2

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.

SERVICING PRECAUTIONS

SECTION 1 GENERAL

LGE Internal Use Only

Only for training and service purposes

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 (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.

LGE Internal Use Only

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 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.

LGE Internal Use Only

Only for training and service purposes

1-5

LOCATION OF USERS CONTROLS

FRONT / BACK PANEL

1. DISPLAY WINDOW

2. • ( )POWER button

• CLOCK button

• TIMER button

• DUBBING (DUBB.) / CD SYNCHRO RECORDING (CD SYNC.) / (ST./MO.) button

3. MULTI JOG

• MANUAL TUNING

• CD SKIP

• CLOCK ADJUST

4. HEADPHONE Jack (PHONES): ø3.5 mm

5. USB ( ) connector

6. • FUNCTION SELECT buttons (TUNER,TAPE, DVD/CD,AUX)

• EQ button

• XTS-PRO button

• USB button

• XDSS Plus button

• Volume control knob

7. PUSH EJECT position (TAPE 1)

8. PUSH EJECT position (TAPE 2)

9. • RECORD/RECORD PAUSE ( REC/ ) button

• TUN.(-/+) buttons -AUTO TUNING / REWIND / FAST FORWARD ( ) -TAPE / SCAN ( ) buttons -CD

• PRESET (-/+) buttons/ TAPE REVERSE PLAY () button (OPTIONAL) / TAPE FORWARD PLAY () button

• STOP ( STOP) button

10.MIC JACKS (MIC1, MIC2): ø6.3 mm : OPTIONAL

11. MIC VOLUME knob

12.Remote control sensor

13.• OPEN/CLOSE ( OP/CL) button

• DISC SKIP (D.SKIP) button

• PLAY MODE, DEMO button

• SET/CD , RDS (OPTIONAL) button

14.DISC DOOR

15.• COMPONENT VIDEO OUT (PROGRESSIVE SCAN) (Y Pb Pr) Connector

• OUT Connector

16.• FM/AM ANTENNA Connector

• AUXILIARY INPUT (AUX IN) connector

17.POWER CORD

18.SPEAKER Connectors (MDT352 Model)

19.SPEAKER Connectors (MDD262 Model)

1

2

3

4 5

6

7

14

13

12

15 11 10

16

9

8

17

MDT352 Model

MDD262 Model

18

19

LGE Internal Use Only

1-6

1. POWER button

2. FUNCTION SELECT buttons (TUNER/BAND,DVD, AUX, USB)

3. NUMERIC buttons (0-9)

4. TAPE FUNCTION buttons

• REVERSE PLAY ( )

• PLAY ( )

• REWIND/ FAST FORWARD PLAY ( )

• TAPE 1-2 SELECT buttons (1-TAPE-2)

• RECORD/ RECORD PAUSE ( / )

• TAPE STOP ( )

5. SETUP button

6. • ARROW buttons ( / )

(Selects an option in the menu)

• PRESET (-/+) buttons ( )

• TUN. (-/+) buttons ( )

7. SELECT/ENTER button

8. MENU button (Use the MENU button to display the menu screen included on DVD video discs.)

9. STOP ( ), PAUSE( )/ STEP, PLAY ( ) buttons

10.PROG./MEMO., REPEAT, REPEAT A-B buttons

11. EQ ,XTS-Pro, SOUND,AUDIO, SUBTITLE (S-TITLE), SHADOW, CLEAR buttons

12.ECHO VOL. ( ) buttons

13.MIC VOL. ( ) buttons

14.RDS, PTY buttons - OPTIONAL

15.XDSS plus, VSM (Virtual Sound Matrix), ZOOM, RETURN ( ) buttons

16.• MARKER, SEARCH, MUTE( ) buttons

• -SCAN+ ( ) / -SKIP+ ( )

17.VOLUME -/+ buttons

18.TITLE button (Use the TITLE button to display the title screen included on DVD video discs.)

19.DISPLAY button

20.DIMMER button

21.SLEEP button

22.DISC SKIP (D.SKIP) button

REMOTE CONTROL

PRESET + +

PRESET - -

SETUP

SCAN

MENU

REPEA

MARKER

SEARCH

REPEA

A-B

PROG./MEMO.

ZOOM

EQ

AUDIO

S-TITLE

RETURN

RDS

PTY

CLEAR

TITLE

DISPLA

SLEEP

DIMMER

AUX

DVD

POWER

MUTE

TUNER/BAND

USB

D.SKIP

OP

PLA

AUSE/STEP

ECHO VOL.

MIC VOL.

TUN. -

TUN. +

1 -

APE - 2

XTS Pro

XDSS plus

VSM

SOUND

SKIP

POWER

1

2

3

4

5

6

7

8

9

10

11

12

TUNER/BAND

1 -

SETUP

TUN. -

MENU

STSTOP

PROG./MEMO.

REPEA

T A-B

EQ

SOUND

S-TITLE

ECHO VOL.

TAPE - 2

PAUSE/STEP

T

MARKER

XTS Pro

AUDIO

CLEAR

DVD

PRESET

SELECT /ENTER

PRESET

SCAN

SKIP

AUX

PLA

Y

SEARCH

XDSS plus

RETURN

RDS

DIMMER

DISPLA

MIC VOL.

D.SKIP

USB

SLEEP

TUN. +

TITLE

MUTE

VSM

ZOOM

PTY

22

21

20

Y

19

18

17

16

15

14

13

LGE Internal Use Only

Only for training and service purposes

1-7

SPECIFICATIONS

• GENERAL

Power supply Refer to the main label. Power consumption Refer to the main label. Net Weight 8.65kg (MDT352)

5.9kg (MDD262)

External dimensions

(W x H x D)

280 X 365 X 370mm

• TUNER/AMPLIFIER

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 140 ~ 10000Hz

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

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

Output Power Front: 130W + 130W (4Ω, THD 10%)(MDD262)

100W + 100W (4Ω, THD 10%)(MDT352)

Subwoofer: 150W (3Ω, THD 10%)(MDT 352)

T.H.D 0.5% Frequency Response 42 ~ 20000Hz Signal-to-noise ratio 75dB

• DVD/VCD/CD PLAYER • CASSETTE TAPE PLAYER

Frequency response (audio) 40 ~ 20000Hz Tape Speed 3000 ± 3% Signal-to-noise ratio (audio) More than 75dB (1kHz) (MTT-111. Signal-to-noise ratio (video) More than 55dB (1kHz) NORMAL-SPEED) Dynamic range (audio) More than 75dB Wow Flutter 0.25% Video output 1.0V (p-p), 75Ω (MTT-111, JIS-WTD) S-video output (Y) 1.0V (p-p), 75Ω F.F/REW. Time 120sec (C-60)

(C) 0.3V (p-p), 75Ω Frequency Response 250 ~ 8000Hz

Component Video output (Y) 1.0V (p-p), 75Ω Signal to Noise Ratio 43dB

(Pb)/(Pr) 0.7V (p-p), 75Ω Channel Separation 45dB (P/B)/45dB (R/P)

Erase Ratio 55dB (MTT-5511)

• SPEAKERS

Speaker Name Front Speaker (L/R) (MDS352V / MDS262V) Type Bass Reflex 2Way 3Speaker Impedance 4Ω Frequency Response 55 ~ 20000Hz Sound Pressure Level 82dB/W (1m) Rated Input Power 130W Max. Input Power 260W Net Dimensions (W x H x D) 212 X 414 X 305mm Net Weight 6.3kg

Speaker Name Subwoofer (MDS352W) Type Bass Reflex 1Way 1Speaker Impedance 3Ω Frequency Response 50 ~ 1500Hz Sound Pressure Level 82dB/W (1m) Rated Input Power 180W Max. Input Power 360W Net Dimensions (W x H x D) 212 X 414 X 305mm Net Weight 6.3kg

LGE Internal Use Only

1-8

MEMO

LGE Internal Use Only

Only for training and service purposes

450

250

263

262

273

455

450

H

K

A

B

E

N

C

F

G

J

I

A26

A40

A47

A46

266

305

267

289

456

250

264

452

458

450

250

290

454

450

A00

257

255

259

A43

A44

450

CABLE4

CABLE3

CABLE1

CABLE5

CN201

P9701

P9702

260

MAIN

SMPS

291

B

M

A

L

C

O

D

K

H

L

J

D

I

M

A41

450

CABLE2

P5701

DVD

FRONT

450

282

255

256

253

254

250

251

252

450

252

258

SECTION 2 EXPLODED VIEWS

CABINET AND MAIN FRAME SECTION

2-1 2-2

LGE Internal Use Only

001

A00

002

037

007

006

008

016

017

018

019

020

003

009

A02

A01

011

013

022

025

015

023

BRASS MOTOR PULLEY MAYBE CHANGED FOR WOW FLUTTER WHEN NECESSARY

RING FW MAYBE ADDED FOR WOW FLUTTER WHEN NECESSARY

TAPE DECK MECHANISM EXPLODED VIEW

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

LGE Internal Use Only

2-3 2-4

Only for training and service purposes

2-5 2-6

A00

RING FW MAYBE ADDED FOR WOW FLUTTER WHEN NECESSARY

013

011

009

003

008

015

022

023

024

016

017

018

019

020

007

A03

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

LGE Internal Use Only

DVD MECHANISM EXPLODED VIEW

416

159

A26

151

417

167

416

177

166

164

417

422

165

440

438

172

175

163

170

419

168

155

417

162

153

173

156

418

169C

012A

169

169A

418

169B

181

A30

430

012A

430

036

035

LGE Internal Use Only

180

417

035A

438

2-7 2-8

Only for training and service purposes

A80A

A80R

A80L

A80BR

A80BL

WIRE80

WIRE81

850

855

856

857

858

860

861

863

859

851

853

852

854

862

SPEAKER EXPLODED VIEW

1. MODEL : MDS352V (FRONT SPEAKERS)

2-9 2-10

LGE Internal Use Only

2. MODEL : MDS352W (SUBWOOFER)

A90B

A90A

WIRE90

950

A90

951

952

956

953

954

955

958

959

957

LGE Internal Use Only

2-11 2-12

Only for training and service purposes

2-13

PACKING ACCESSORY VIEW

LGE Internal Use Only

3-1

AUDIO ELECTRICAL TROUBLESHOOTING GUIDE

SECTION 3 AUDIO PART ELECTRICAL

1. POWER (SMPS)

POWER (SMPS)

OK

YES

Replace IC 901,902

Check IC901, 902

Check the fuse

F901

NONO

NO

YES

Check short of

P9701, P9702 line

Replace the fuse

Check

the DC V of C905.

If DC V is over

400V

NO

Check BD901, LF901, 902

Check the

DC V of C981, C945.

If DC V is 6.1V

NO

Check short of P9702 line

YES

Chcek the

DC V of C950, C951

If DC V is in

31.5V

NO

Check short of P9701 line

Chcek the

DC V of C909, C903,

C921 If DC V is in 14~19V

and it is steady.

YES

LGE Internal Use Only

Only for training and service purposes

3-2

2. P-SENS

P-SENS

YES

Check

the PIN6 of P9702

If DC V is over 5.6V

Check power circuit Troubleshooting

NO

OK

3. VKK CHECK

VKK check

YES

Check

the PIN3 of P9702

If DC V is over -28V ±2

Check power circuit Troubleshooting

NO

OK

4. MICOM PART CHECK I

MICOM part check I

OK OK

YES

Check P-SENS

(P7904)_PIN6.

NO

Refer to

SMPS troubleshooting.

YES

Check both

end voltage of IC101

(KIA7042).

Check

if input voltage of

IC101(KIA7042) is

over 5V.

YES

NO

Check the

periphery of IC101

(KIA7042).

NO

YES

Check if IC101(KIA7042) of output voltage is over 4.3V.

Check voltage of IC100

78KO/KF2_PIN1.

NO

Replace IC101

(KIA7042).

LGE Internal Use Only

3-3

5. MICOM PART CHECK II

MICOM part check II

X101 : 32.768kHz

X100 : 9.8304MHz

Check the operation.

Check

Q101_ emitter/collector

5V.

Check Q102_base

0.6V HIGH.

Check if IC103_PIN8 and

IC100_PIN19, 20, 59 are 5V.

NO NO

YES

Check if

voltage of P7904_PIN5

is 5.6V.

NO

Refer to

SMPS troubleshooting.

YES

OK

YES

Check

both end voltage of

D101

YES

Check D101.

NO

Check if output of

D101(1SR35) is 5V.

YES

Check IC101.

Q102_collector 0.6V LOW.

OK

Check if output of IC101

(KIA7042) is over 4.3V.

OK

NO

Replace IC101.

NO

Replace D101.

YES

Check Q102.

OK

NO

Replace Q102.

LGE Internal Use Only

Only for training and service purposes

3-4

Check

IC100(78KOKF2)_

PIN 22, 24

OK

YES

Refer to

micom troubleshooting

Check micom

voltage 5V.

PIN22

DATA PIN24 CLK

NONO

YES

Replace micom.

Check micom.

NO

YES

OK

6. IC103(KS4CD21CS) CHECK

LGE Internal Use Only

3-5

FLD display check

YES

Replace P3702.

Check each

PIN voltage.

NO

YES

OK

Replace IC301.

Check IC301.

NO

YES

Replace IC100FLD light on?

Check IC100.

NO

YES

OK

Refer to SMPS

7. FLD DISPLAY CHECK

YES

Check

P7904_PIN1, 2, 3 voltage

input.

NO

Check P3702 connection.

NO

If voltage is not 5V,

check input and output

of D319(1SR35).

YES

Check

P3702 connection

and power. Pin1 : FL-22 Pin2 :

FL+26 Pin3 : VKK- over

28V. Pin5 :

5.6V

YES

OKOK

76 PIN - > DO - - >

Check data input.

NO

IC100

75 PIN - > STB

77 PIN - > 4PIN DI

78 PIN - > 1PIN CLK

Check data input.

IC100 - >

Check IC301

DATA communication.

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

CLK

Check

IC301(PT6324) voltage.

Pin50 VKK : -28V

PIN9.52 : +5V

Check if both end votage

of F1, F2 are over 3.7V.

VKK : over 28V.

LGE Internal Use Only

Only for training and service purposes