LG DK7711PM User manual

SERVICE MANUAL
LG DK7711PM
MODEL

SECTION 1
SUMMARY
CONTENTS
PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS ........................... 1-3
SERVICING PRECAUTIONS .................................................................................................. 1-4
• General Servicing Precautions
• Insulation Checking Prodedure
• Electrostatically Sensitive Devices
SPECIFICATIONS ...................................................................................................................... 1-5

1-3
CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY,
NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFAC-
TURER’S APPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLY
VOID THE WARRANTY, BUT MAY LEAD TO YOUR BEING LIABLE FOR ANY
RESULTING PROPERTY DAMAGE OR USER INJURY.
SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE
THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING SAFETY
CHECKS AND SERVICING GUIDELINES. TO DO OTHERWISE,
INCREASES THE RISK OF POTENTIAL HAZARDS AND INJURY TO THE
USER.
WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR PROTEC-
TION FROM A.C. LINE SHOCK.
SAFETY CHECKS
AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRCTED. A
CHECK SHOULD BE MADE OF THE FOLLOWING.
SUBJECT : FIRE & SHOCK HAZARD
1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN SUCH A WAY
AS TO AVOID POSSIBILITY OF ADJACENT COMPONENT SHORTS.
THIS IS ESPECIALLY IMPORTANT ON THOSE MODULES WHICH ARE
TRANSPORTED TO AND FROM THE REPAIR SHOP.
2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE DEVICES
SUCH AS INSULATORS, BARRIERS, COVERS, SHIELDS, STRAIN
RELIEFS, POWER SUPPLY CORDS, AND OTHER HARDWARE HAVE
BEEN REINSTALLED PER ORIGINAL DESIGN. BE SURE THAT THE
SAFETY PURPOSE OF THE POLARIZED LINE PLUG HAS NOT BEEN
DEFEATED.
3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE COLD
SOLDER JOINTS, SOLDER SPLASHES OR SHARP SOLDER POINTS.
BE CERTAIN TO REMOVE ALL LOOSE FOREIGN PARTICLES.
4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR DETERIORATION
TO PARTS AND COMPONENTS. FOR FRAYED LEADS, DAMAGED
INSULATION (INCLUDING A.C. CORD). AND REPLACE IF NECESSARY
FOLLOW ORIGINAL LAYOUT, LEAD LENGTH AND DRESS.
5. NO LEAD OR COMPONENT SHOULD TOUCH A RECIVING TUBE OR
A RESISTOR RATED AT 1 WATT OR MORE. LEAD TENSION AROUND
PROTRUNING METAL SURFACES MUST BE AVOIDED.
6. ALL CRITICAL COMPONENTS SUCH AS FUSES, FLAMEPROOF
RESISTORS, CAPACITORS, ETC. MUST BE REPLACED WITH EXACT
FACTORY TYPES, DO NOT USE REPLACEMENT COMPONENTS
OTHER THAN THOSE SPECIFIED OR MAKE UNRECOMMENDED CIR-
CUIT MODIFICATIONS.
7. AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM AN A.C.
LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OF THE CABI-
NET, (THE CHANNEL SELECTOR KNOB, ANTENNA TERMINALS. HAN-
DLE AND SCREWS) TO BE SURE THE SET IS SAFE TO OPERATE
WITHOUT DANGER OF ELECTRICAL SHOCK. DO NOT USE A LINE
ISOLATION TRANSFORMER DURING THIS TEST USE AN A.C. VOLT-
METER, HAVING 5000 OHMS PER VOLT OR MORE SENSITIVITY, IN
THE FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT RESIS-
TOR, PARALLELED BY A .15 MFD. 150.V A.C TYPE CAPACITOR
BETWEEN A KNOWN GOOD EARTH GROUND (WATER PIPE, CON-
DUIT, ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME.
MEASURE THE A.C. VOLTAGE ACROSS THE COMBINATION OF 1500
OHM RESISTOR AND .15 MFD CAPACITOR. REVERSE THE A.C. PLUG
AND REPEAT A.C. VOLTAGE MEASUREMENTS FOR EACH EXPOSED
METALLIC PART. VOLTAGE MEASURED MUST NOT EXCEED 75
VOLTS R.M.S. THIS CORRESPONDS TO 0.5 MILLIAMP A.C ANY
VALUE EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL SHOCK
HAZARD AND MUST BE CORRECTED IMMEDIATELY.
SUBJECT: 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 MAG-
NITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIAN-
GLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO
THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN
SERVICE LITERATURE.
SUBJECT : X-RADIATION
1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PER-
SONNEL COVER THE SUBJECT OF X-RADIATION. THE ONLY POTEN-
TIAL SOURCE OF X-RAYS IN CURRENT T.V. RECEIVERS IS THE PIC-
TURE TUBE. HOWEVER, THIS TUBE DOES NOT EMIT X-RAYS WHEN
THE HIGH VOLTAGE IS AT THE FACTORY SPECIFIED LEVEL. THE
PROPER VALUE IS GIVEN IN THE APPLICABLE SCHEMATIC. OPERA-
TION AT HIGHER VOLTAGES MAY CAUSE A FAILURE OF THE PIC-
TURE TUBE OR HIGH VOLTAGE SUPPLY AND, UNDER CERTAIN CIR-
CUMSTANCES, MAY PRODUCE RADIATION IN EXCESS OF DESIR-
ABLE LEVELS.
2. ONLY FACTORY SPECIFIED C.R.T. ANODE CONNECTORS MUST BE
USED. DEGAUSSING SHIELDS ALSO SERVE AS X-RAY SHIELD IN
COLOR SETS, ALWAYS RE-INSTALL THEM.
3. IT IS ESSNTIAL THAT SERVICE PERSONNEL HAVE AVAILABLE AN
ACCURATE AND RELIABLE HIGH VOLTAGE METER. THE CALIBRA
TION OF THE METER SHOULD BE CHECKED PERIODICALLY
AGAINST A REFERENCE STANDARD, SUCH AS THE ONE AVAILABLE
AT YOUR DISTRIBUTOR.
4. WHEN THE HIGH VOLTAGE CIRCUITRY IS OPERATING PROPERLY
THERE IS NO POSSIBILITY OF AN X-RADIATION PROBLEM. EVERY
TIME A COLOR CHASSIS IS SERVICED. THE BRIGHTNESS SHOULD
BE RUN UP AND DOWN WHILE MONITORING THE HIGH VOLTAGE
WITH A METER TO BE CERTAIN THAT THE HIGH VOLTAGE DOES
NOT EXCEED THE SPECIFIED VALUE AND THAT IT IS REGULATING
CORRECTLY, WE SUGGEST THAT YOU AND YOUR SERVICE ORGA-
NIZATION REVIEW TEST PROCEDURES SO THAT VOLTAGE REGU-
LATION IS ALWAYS CHECKED AS A STANDARD SERVICING PROCE-
DURE. AND THAT THE HIGH VOLTAGE READING BE RECORDER ON
EACH CUSTOMER’S INVOICE.
5. WHEN TROUBLESHOOTING AND MAKING TEST MEASUREMENTS IN
A PRODUCT WITH A PROBLEM OF EXCESSIVE HIGH VOLTAGE,
AVOID BEING UNNECESSARILY CLOSE TO THE PICTURE TUBE AND
THE HIGH VOLTAGE SUPPLY. DO NOT OPERATE THE PRODUCT
LONGER THAN IS NECESSARY TO LOCATE THE CAUSE OF EXCES
SIVE VOLTAGE.
6. REFER TO HV. B+ AND SHUTDOWN ADJUSTMENT PROCEDURES
DESCRIBED IN THE APPROPRIATE SCHEMATIC AND DIAGRAMS
(WHERE USED).
SUBJECT: IMPLOSION
1. ALL DIRECT VIEWED PICTURE TUBES ARE EQUIPPED WITH AN INTE
GRAL IMPLOSION PROTECTION SYSTEM, BUT CARE SHOULD BE
TAKEN TO AVOID DAMAGE DURING INSTALLATION, AVOID
SCRATCHING THE TUBE. IF SCRATCHED REPLACE IT.
2. USE ONLY RECOMMENDED FACTORY REPLACEMENT TUBES.
SUBJECT : TIPS ON PROPER INSTALLATION
1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS, CUBBY-
HOLE OR CLOSELY FITTING SHELF SPACE. OVER OR CLOSE TO
HEAT DUCT, OR IN THE PATH OF HEATED AIR FLOW.
2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIO
INSTALLATIONS WHERE DEW IS A FACTOR, NEAR STEAM RADIA-
TORS WHERE STEAM LEAKAGE IS A FACTOR, ETC.
3. AVOID PALCEMENT WHERE DRAPERIES MAY OBSTRUCT REAR
VENTING. THE CUSTOMER SHOULD ALSO AVOID THE USE OF DEC-
ORATIVE SCARVES OR OTHER COVERINGS WHICH MIGHT
OBSTRUCT VENTILATION.
4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMER-
CIAL MOUNTING KIT. MUST FOLLOW THE FACTORY APPROVED
MOUNTING INSTRUCTIONS A PRODUCT MOUNTED TO A SHELF OR
PLATFORM MUST RETAIN ITS ORIGINAL FEET (OR THE EQUIVALENT
THICKNESS IN SPACERS) TO PROVIDE ADEQUATE AIR FLOW
ACROSS THE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERS
MUST NOT TOUCH ANY PARTS OR WIRING. PERFORM LEAKAGE
TEST ON CUSTOMIZED INSTALLATIONS.
5. CAUTION CUSTOMERS AGAINST THE MOUNTING OF A PRODUCT ON
SLOPING SHELF OR A TILTED POSITION, UNLESS THE PRODUCT IS
PROPERLY SECURED.
6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE ON ITS
MOUNTING TO THE CART. CAUTION THE CUSTOMER ON THE HAZ-
ARDS OF TRYING TO ROLL A CART WITH SMALL CASTERS ACROSS
THRESHOLDS OR DEEP PILE CARPETS.
7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR STAND
WHICH HAS NOT BEEN LISTED BY UNDERWRITERS LABORATORIES,
INC. FOR USE WITH THEIR SPECIFIC MODEL OF TELEVISION
RECEIVER OR GENERICALLY APPROVED FOR USE WITH T.V.’S OF
THE SAME OR LARGER SCREEN SIZE.
8. CAUTION CUSTOMERS AGAINST THE USE OF EXTENSION CORDS,
EXPLAIN THAT A FOREST OF EXTENSIONS SPROUTING FROM A SIN-
GLE OUTLET CAN LEAD TO DISASTROUS CONSEQUENCES TO
HOME AND FAMILY.
PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS
A.C. VOLTMETER
GOOD EARTH GROUND
SUCH AS THE WATER
PIPE. CONDUIT. ETC
PLACE THIS PROBE
ON EACH EXPOSED
METAL PART

1-4
SERVICING PRECAUTIONS
CAUTION : Before servicing the DVD covered by this service
data and its supplements and addends, read and follow the
SAFETY PRECAUTIONS. NOTE : if unforeseen circum-
stances create conflict between the following servicing pre-
cautions and any of the safety precautions in this publica-
tions, always follow the safety precautions.
Remembers Safety First:
General Servicing Precautions
1. Always unplug the DVD AC power cord from the AC
power source before:
(1) Removing or reinstalling any component, circuit board,
module, or any other assembly.
(2) Disconnection or reconnecting any internal electrical
plug or other electrical connection.
(3) Connecting a test substitute in parallel with an elec-
trolytic capacitor.
Caution : A wrong part substitution or incorrect
polarity installation of electrolytic capacitors may result
in an explosion hazard.
2. Do not spray chemicals on or near this DVD or any of
its assemblies.
3. Unless specified otherwise in this service data, clean
electrical contacts by applying an appropriate contact
cleaning solution to the contacts with a pipe cleaner,
cotton-tipped swab, or comparable soft applicator.
Unless specified otherwise in this service data, lubrication
of contacts is not required.
4. Do not defeat any plug/socket B+ voltage interlocks with
whitch instruments covered by this service manual might
be equipped.
5. Do not apply AC power to this DVD and/or any of its
electrical assemblies unless all solid-state device heat
sinks are cerrectly installed.
6. Always connect test instrument ground lead to the
appropriate ground before connection the test instrument
positive lead. Always remove the test instrument ground
lead last.
Insulation Checking Procedure
Disconnect the attachment plug from the AC outlet and turn
the power on. Connect an insulation resistance meter(500V)
to the blades of the attachment plug. The insulation resis-
tance between each blade of the attachment plug and acces-
sible conductive parts (Note 1) should be more than 1M-
ohm.
Note 1 : Accessible Conductive Parts including Metal pan-
els, Input terminals, Earphone jacks, etc.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged
easily by static electricity. Such components commonly are
called Electrostatically Sensitive (ES) Devices. Examples of
typical ES 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 compo-
nent or semiconductor-equipped assembly, drain off any
electrostatic charge on your body by touching a known
earth ground. Alternatively, obtain and wear a commer-
cially 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 ES
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 grouned-tip soldering iron to solder or unsolder
ES devices.
4. Use only an anti-static solder removal device. Some
solder removal devices not classified a “anti-static”can
generate electrical charges sufficient to damage ES
devices.
5. Do not use freon-propelled chemicals. These can
generate electrical charge sufficient to damage ES
devices.
6. Do not remove a replacement ES device from its protec
tive package until immediately before you are ready to
install it. (Most replacement ES devices are packaged with
leads electrically shorted together by conductive foam,
aluminum foil, or comparable conductive material).
7. Immediately before removing the protective material from
the leads of a replacement ES device, touch the protective
material to the chassis or circuit assembly into which the
device will be installed.
Caution : Be sure no power is applied to the chassis or
circuit, and observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Normally harmless motion such
as the brushing together of your clothes fabric or the lifting
of your foot from a carpeted floor can generate static elec-
tricity sufficient to damage an ES device.)

2-1
SECTION 2
CABINET & MAIN CHASSIS
CONTENTS
1. EXPLODED VIEWS ................................................................................................................2-2
1. Cabinet and Main Frame Section ...........................................................................................2-2
2. Deck Mechanism Section........................................................................................................2-4
3. Packing Accessory Section....................................................................................................2-5

2-2
EXPLODED VIEWS
1. Cabinet and Main Frame Section
463 463
250
A00
463
463
300
283
279
280
A42
A49
A47
A48
A44
A43
A46
260
261
261
463
320
463
467
463
465
452
A41
SCART&5.1CH
MODEL
ONLY
OPTIONAL PART
KARAOKE MODEL
ONLY
KARAOKE MODEL
ONLY
A
5
4
3
2
1
BCD

2-4
2. Deck Mechanism Section
001
003
004 431
026
021 023
025
436
436
436
022
024A
024B
024A
435
022A
032
024
027
028
031
030
434
A02
A03
A01
A00
020
011A
010
015
015A
015B
015C
017
013
014
018
011
029
012
430
431
431
012
430
433
002
A
5
4
3
2
1
BCD

3. Packing Accessory Section
BATTERY
808
PACKING SHEET
804
PACKING
OPTIONAL PARTS
803
806
820
OWNER'S MANUAL
RF CABLE
810 CABLE SET ASS'Y
801
REMOCON
900
BOX CARTON
802
PACKING
803
811
812
PLUG ASS'Y 1WAY(YELLOW)
PLUG ASS'Y 1WAY(BLACK)
PLUG ASS'Y 2WAY

3-1
SECTION 3
ELECTRICAL
CONTENTS
ELECTRICAL TROUBLESHOOTING GUIDE......................................................................3-2
1. Power check flow.....................................................................................................................3-2
2. System operation flow ............................................................................................................3-3
3. Test & debug flow ....................................................................................................................3-4
4. Karaoke flow ..........................................................................................................................3-10
DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING ....................3-11
1. SYSTEM 27MHz CLOCK,RESET,FLASH R/W SIGNAL........................................................3-11
2. SDRAM CLOCK......................................................................................................................3-13
3. TRAY OPEN/CLOSE SIGNAL ................................................................................................3-13
4. SLED CONTROL RELATED SIGNAL (NO DISC CONDITION) ............................................3-15
5. LENS CONTROL RELATED SIGNAL(NO DISC CONDITION) .............................................3-15
6. LASER POWER CONTROL RELATED SIGNAL(NO DISC CONDITION)............................3-16
7. DISC TYPE JUDGEMENT WAVEFORM ................................................................................3-16
8. FOCUS ON WAVEFORM........................................................................................................3-18
9. SPINDLE CONTROL WAVEFORM (NO DISC CONDITION).................................................3-19
10. TRACKING CONTROL RELATED SIGNAL(System checking).........................................3-20
11. RF WAVEFORM ....................................................................................................................3-21
12. MT1379 AUDIO OPTICAL AND COAXIAL OUTPUT (ASPDIF)..........................................3-21
13. MT1379 VIDEO OUTPUT WAVEFORM................................................................................3-22
14. AUDIO OUTPUT FROM AUDIO DAC ..................................................................................3-23
BLOCK DIAGRAMS ..................................................................................................................3-25
1. Overall Block Diagram ..........................................................................................................3-25
2. Power(SMPS) Block Diagram ...............................................................................................3-26
3. SERVO Block Diagram ..........................................................................................................3-27
4. MPEG & MEMORY Block Diagram .......................................................................................3-28
5. VIDEO & AUDIO Block Diagram ...........................................................................................3-29
6. Karaoke Block Diagram ........................................................................................................3-30
CIRCUIT DIAGRAMS................................................................................................................3-31
1. Power(SMPS) Circuit DIAGRAM...........................................................................................3-31
2. SYSTEM Circuit DIAGRAM ...................................................................................................3-33
3. RF & SERVO Circuit DIAGRAM ............................................................................................3-35
4. TIMER, 5.1CH, SCART, KARAOKE Circuit DIAGRAM ........................................................3-37
5. AV/JACK Circuit DIAGRAM...................................................................................................3-39
•CIRCUIT VOLTAGE CHART ....................................................................................................3-41
PRINTED CIRCUIT DIAGRAMS ............................................................................................3-45
1. MAIN P.C.BOARD ...................................................................................................................3-45
2. KEY P.C.BOARD.....................................................................................................................3-47
3. TIMER P.C.BOARD .................................................................................................................3-47
4. SCART & 5.1CH P.C.BOARD(OPTIONAL PART) .................................................................3-49
5. POWER P.C.BOARD...............................................................................................................3-49
6 KARAOKE P.C.BOARD (KARAOKE MODEL ONLY) ............................................................3-50

3-2
ELECTRICAL TROUBLESHOOTING GUIDE
No 5V_A .
No 5.2VA.
Is 5.2VA section working?
Is 5.2V present at emitter
of Q107?
Replace Q107.
Is there a DC voltage At
(+) terminal of BD101?
Is there a DC voltage at
R101?
Replace IC101.
Check F101
1. Power check flow
No VF+
Is 5.2VA section working?
Replace D109.
Check F102
NO
NO
YES
YES YES
YES
Replace R101.
YES
Replace BD101.
YES
YES
A. B.
NO
NO
NO
NO

3-3
2. System operation flow
Power On
No
Yes
Yes
Yes
No
No
No
Show LOGO
Tray Closed?
Tray Close to Closed position
SLED Moves to Inner Position
Recieve
OPEN/ CLOSE
Key?
Receive
CLOSE Key?
1. Stop Playback & Open Tray
2. Display tray open message & LOGO
1. Execute Pressed Key & IR Key
2. Systemoperati on Routi ne Loop
1. Judge whether have disc and disc type
2. Jump to related disc reading procedure
SLED at Inner
Side?
1. 8032 initializes SERVO, DSP & RISC registers
2. Write RISC code to SDRAM
3. Reset RISC

3-4
3. Test & debug flow
TEST
Check the POWER PART
No
Yes
No
Yes
No
No
No
Yes
Yes
Check the POWER PART
Check the regulators or diode( D670).
Check the cable connection Front
Panel & Communication Signal
1. Check 27MHz system clock.
2. Check systemreset circuit.
3. Check FLASH R/Wenable signal PRD,
RWR.
4. Check RS232 SIGNALS.
5. Check FLASH Memory related circui t.
Check the
AC Vol tage
Power PCBA (110V
or 220V)
Switch on the Power PCBA
Is
the DC Vol tage
outputs OK?
(5V, 3.3V, 8V, 12V)
Is 3.3V and 2.5V DC
outputs normal on main
PCBA?
Update
FLASH(IC5A1)
successfully?
Replace FLASH( IC5A1)
A
Communication between
IC901 & MT1379 is normally?
Connect to PC RS232 Cable and
update the FLASH memory code.
Make sure the main
PCBA don’t

3-5
A
B
RESET or Power On.
Show LOGO?
Flash
Memory operates
properly?
Check connecti on lines between FLASH
& MT1379 and the FLASH access time
whether is sui table or not.
SDRAM
works properl y?
MT1379
VIDEO outputs
properly?
Have
TV signal output?
Check AV cable
connection to TV set .
Check the load OPEN &
CLOSE switch
Check the Tray control IO pins
on MT1376 & MT1379.
Check the Tray control amplifying
circuit on Motor driver.(IC202)
Does
Tray move inside
when it is not at
closed position?
Normal
TROUT & TRIN
signals?
Normal
TRCLOSE &
TROPEN signal?
Normal
LOAD+ & LOAD-
signal ?
Check the cable connection between
main PCBA and loader. (MECHA)
Check connection lines between
SDRAM(IC502,IC503) & MT1379 and the
SDRAM is damaged.
Check the rel ated ci rcui t of MT1379.
(IC501 PIN 161,166, 168 check)
Check the fi l teri ng and amp ci rcui t of
TV si gnal .(IC604)

3-6
B
No
YesYes
Yes
No
Yes
Yes
Yes
No
Yes
No
No
No
Does
the SLED move
to inner side when it is at
outter positi on?
Motor Driver STBY
Pin is High?
Motor Driver STBY
Pin is High?
SL+ and SL- output
properl y?
Optical
Lens has movements
for searching
Focus?
Proper F+
& F- outputs?
Check cable connect on with
pick-up head.
Proper FOSO outputs
to motor driver?
Check FOSO connection on
MT1379 and motor dirver.
Check the amp circuit on
motor dirver.
C
Check the cable connection
with MECHA.
Do not put in disc and tray
close.
Check the connection line of
STBY signal .
Check the rel ated circuit of
FMSO.
Check the amp circuit on
motor driver.

3-7
C
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Laser turns on when
reading disc? LD01 or LD02 output
properly?
Check the laser power circuit
on MT1336 and connecting to
power transistor. (Q204, Q205)
Check therel ated ci rcuit on
laser power transi stor
Check the related circuit
on MT1336 RFL signal .
Collector
voltage of power
transistor is OK?
( Q204, Q205)
Check cable connection between
transistor couput and pick-up head.
Laser off
Proper RFL signal
on MT1336?
Proper
DMSO signal on
MT1379
Check DMSO related
circuit on MT1379.
Check the spindle control
amp circuit of motor driver.
SP+ & SP- output
properly?
Check the cable connection
between spindle and main PCBA.
Check the RFL connection
between MT1336 and MT1379.
Put disc in?
Disc ID is correct?
Does spindle rotate?
D

3-8
D
Yes
Yes
No No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
Focus ON OK?
Track On OK?
Disc is play?
E
Proper
signals on A, B, C,
D of MT1336
Check connections between
MT1336 and pick-up head.
Proper FEO signal
on MT1336?
Proper FEO signal
on MT1336?
Check the related circuit
on MT1336 FEO sugnal .
Check the related
circuit on MT1336
Properly TRSO signal
on MT1379?
T+ & T- output
properly?
Check the TRSO connection
on MT1379 and motor dirver.
Check the tracking control
amp circuit on motor driver.
Check cable connection on
pick-up head.
Check RF signal waveform.
Check FEO connection
between MT1336 and MT1379

3-9
E
Normal
Audio output
when disc playback?
Normal
IR. VFD & Front
pannel key
functions?
TEST END
Audio
DAC received
correct data stream?
Normal
Audio DAC
out? (IC601)
Check Audio filter, amplify, mute
circuit. (IC602 Application circuit)?
Check the cable connection
on Front pannel.
Check connection between MT1379
& Audio DAC. (Check VRST#, ACLK,
ABCK, ASDAT3)
Check the related circuit of
Audio DAC. (Check Audio
out Pin 14, 15,18,19)
Check communi cation lines
on MT1379.
Communications
between IR.VFD Front pannel key
& MT1379 & Front u-com(IC901)
is normally?

3-10
4. KARAOKE Flow (KARAOKE MODEL ONLY)
Is the Mic signal at the
IC801 pin3.
Is the Mic signal at the
IC801 Pin 2.
Is the Mic signal at the
IC801 Pins3, 7 normal?
Is the Digital
signal output at the
IC5K1 Pin1.
Replace IC501.
Replace the IC5K1.
Check pattern.
Replace the VR801.
Replace IC801.
Replace the mic jack
Start
Insert the Mic jack
Does the Mic
signal input the IC501
Pin152.
NO
NO
NO
NO
NO
YES YES
YES
YES

3-11
DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING
1. SYSTEM 27MHz CLOCK,RESET,FLASH R/W SIGNAL
1) MT1379 main clock is at 27MHz(X501)
3.8V, 27MHz
FIG 1-1
2) MT1379 & MT1336 reset is high active.
PWR_CTL(CN505 PIN 7)
5.2VA
Power Cord in
M_RESET(CN505 PIN 9)
URST(IC501 PIN 188)
FIG 1-2

3-12
3) RS232 waveform during procedure(Downloading)
TXD(J6 PIN3)
RXD(J6 PIN 2)
FIG 1-3
4) Flash R/W enable signal during download(Downloading)
FRD(IC5A1 PIN 28)
FWR(IC5A1 PIN 11)
FIG 1-4