LG DVX286 User manual

DVD-VIDEO PLAYER
SERVICE MANUAL
MODELS : DVX286/DV286/DV286K
CAUTION
BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS”
IN THIS MANUAL.
MODELS : DVX286/DV286/DV286K
SERVICE MANUAL
P/N : AFN31629357JANUARY, 2007
http://biz.lgservice.com

CONTENTS
SECTION 1.........SUMMARY
SECTION 2.........CABINET & MAIN CHASSIS
SECTION 3.........ELECTRICAL
SECTION 4.........MECHANISM (DP-11)
SECTION 5.........REPLACEMENT PARTS LIST

1-2
SECTION 1
SUMMARY
CONTENTS
PRODUCT SAFETY SERVICING GUIDELINES FOR DVD PRODUCTS
..................1-3
SERVICING PRECAUTIONS ....................................................................................1-4
• GENERAL SERVICING PRECAUTIONS
• INSULATION CHECKING PRODEDURE
• ELECTROSTATICALLY SENSITIVE (ES) DEVICES
SERVICE INFORMATION FOR EEPROM................................................................1-5
SPECIFICATIONS .....................................................................................................1-6

1-3
PRODUCT SAFETY SERVICING GUIDELINES FOR DVD PRODUCTS
CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY, NEVER
PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFACTURER’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 PROTECTION 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 AWAY 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 CIRCUIT MODIFICATIONS.
7.AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM AN A.C. LEAKAGE TEST
ON ALL EXPOSED METALLIC PARTS OF THE CABINET, (THE CHANNEL
SELECTOR KNOB, ANTENNA TERMINALS. HANDLE 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.
VOLTMETER, HAVING 5000 OHMS PER VOLT OR MORE SENSITIVITY, IN THE
FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT RESISTOR,
PARALLELED BY A .15 MFD. 150.V A.C TYPE CAPACITOR BETWEEN A KNOWN
GOOD EARTH GROUND (WATER PIPE, CONDUIT, 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 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.
SUBJECT : X-RADIATION
1.BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PERSONNEL
COVER THE SUBJECT OF X-RADIATION. THE ONLY POTENTIAL SOURCE OF X-
RAYS IN CURRENT T.V. RECEIVERS IS THE PICTURE 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. OPERATION AT HIGHER VOLTAGES MAY CAUSE A FAILURE OF
THE PICTURE TUBE OR HIGH VOLTAGE SUPPLY AND, UNDER CERTAIN
CIRCUMSTANCES, MAY PRODUCE RADIATION IN EXCESS OF DESIRABLE
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 CALIBRATION 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
ORGANIZATION REVIEW TEST PROCEDURES SO THAT VOLTAGE REGULATION
IS ALWAYS CHECKED AS A STANDARD SERVICING PROCEDURE. 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, CUBBYHOLE 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 RADIATORS WHERE
STEAM LEAKAGE IS A FACTOR, ETC.
3.AVOID PALCEMENT WHERE DRAPERIES MAY OBSTRUCT REAR VENTING. THE
CUSTOMER SHOULD ALSO AVOID THE USE OF DECORATIVE SCARVES OR
OTHER COVERINGS WHICH MIGHT OBSTRUCT VENTILATION.
4.WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMERCIAL
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 HAZARDS 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 SINGLE OUTLET CAN
LEAD TO DISASTROUS CONSEQUENCES TO HOME AND FAMILY.

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
circumstances create conflict between the following
servicing precautions and any of the safety precautions in
this publications, 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
electrolytic 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
resistance between each blade of the attachment plug and
accessible conductive parts (Note 1) should be more than
1Mohm.
Note 1 : Accessible Conductive Parts including Metal panels,
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
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 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
protective 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
electricity sufficient to damage an ES device.)

1-5
SERVICE INFORMATION FOR EEPROM
POWER ON
Press number 0~8, Press charater
A~F (1~6 for a while)
Press pause key once
Change will be applied when power
OFF-->ON.
Use arrow key (F D G E) to move
to approprite position and make
changes
DVD LOGO Status (NO Disk status)
Remotecontrol
Pause key-->1-->4-->7-->2 in order.
MODEL :
NAME HEX
OPT 100
OPT 200
OPT 300
OPT 400
OPT 500
OPT 600
OPT 700
OPT 8 00
DETECT NEW EEPROM
(OPTION EDIT SCREEN)

1-6
SPECIFICATIONS
• GENERAL
Power requirements : AC 200-240V , 50/60Hz
Power consumption : 8W
Dimensions (Approx.) : 430 x 35 x 202mm (17 x 1.4 x 7.9inches) (W x H x D) without foot
Net Weight (Approx.) : 1.9kg (4.2lbs)
Operating temperature : 5°C to 35°C (41°F to 95°F)
Operating humidity : 5% to 90%
• OUTPUTS
VIDEO OUT : 1.0V (p-p), 75Ω, sync negative, RCA jack x 1 / Scart (to TV)
S-VIDEO OUT : (Y) 1.0 V (p-p), 75Ω, negative sync, Mini DIN 4-pin x 1
(C) 0.3 V (p-p), 75Ω
COMPONENT VIDEO OUT : (Y) 1.0 V (p-p), 75Ω, negative sync, RCA jack x 1
(Pb)/(Pr) 0.7 V (p-p), 75Ω, RCA jack x 2
AUDIO OUT : 2.0Vrms (1 KHz, 0 dB), 600Ω, RCA jack (L, R) x 1 / Scart (to TV)
DIGITAL OUT (COAXIAL) : 0.5V (p-p), 75Ω, RCA jack x 1
Scart model only
• SYSTEM
Laser : Semiconductor laser, wavelength 650 nm
Signal system : PAL/NTSC
Frequency response : DVD (PCM 96kHz) : 8Hz to 44kHz
DVD (PCM 48 kHz) : 8Hz to 22kHz
CD : 8Hz to 20kHz
Signal-to-noise ratio : More than 90dB (ANALOG OUT connectors only)
Harmonic distortion : Less than 0.02%
Dynamic range : More than 95dB (DVD/CD)
Accessories : Video cable (1), Audio cable (1), Remote control (1), Batteries (2)
Note : Design and specifications are subject to change without prior notice.

2-1
SECTION 2
CABINET & MAIN CHASSIS
CONTENTS
EXPLODED VIEWS......................................................................................................................2-2
1. CABINET AND MAIN FRAME SECTION .................................................................................2-2
2. DECK MECHANISM SECTION (DP-11) ...................................................................................2-3
3. PACKING ACCESSORY SECTION ..........................................................................................2-4

452
A
C
D
B
A
C
B
D
OPTIONAL PART
463/460
463/460
463
461
462
462
463/460
250
462
A48
A43
462
A44
A49
A42
A41
A46
P101
P8601
CABLE1
CN903
A47
300
A26
283
452
280
279
276
261
261
260
262
320
467
465
261
KARAOKE
MAIN
SMPS
5.1CH
SCART
KEY
TIMER
2-2
EXPLODED VIEWS
1. CABINET AND MAIN FRAME SECTION
275

2-3
2. DECK MECHANISM SECTION (DP-11)
A26
A02
439
018
013
017
014
001
002
003
020
016
015B
015A
435
015
019
440 432
012A
010
439
431
435
030
024
025
036
A03
430
021
012A
012
012
026
A01

2-4
3. PACKING ACCESSORY SECTION

3-1
SECTION 3
ELECTRICAL
CONTENTS
ELECTRICAL TROUBLESHOOTING GUIDE......................................................................3-2
1. POWER CHECK FLOW ..........................................................................................................3-2
2. SYSTEM OPERATION FLOW.................................................................................................3-3
3. SYSTEM TEST FLOW.............................................................................................................3-4
DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGIBG
...........................3-10
1. SYSTEM 27MHZ CLOCK, RESET, FLASH R/W SIGNAL ...................................................3-10
2. SDRAM CLOCK ....................................................................................................................3-12
3. TRAY OPEN/CLOSE SIGNAL...............................................................................................3-12
4. SLED CONTROL RELATED SIGNAL (NO DISC CONDITION)...........................................3-13
5. LENS CONTROL RELATED SIGNAL (NO DISC CONDITION)...........................................3-13
6. LASER POWER CONTROL RELATED SIGNAL (NO DISC CONDITION) .........................3-14
7. DISC TYPE JUDGEMENT WAVEFORM...............................................................................3-14
8. FOCUS ON WAVEFORM ......................................................................................................3-16
9. SPINDLE CONTROL WAVEFORM (NO DISC CONDITION) ...............................................3-17
10. TRACKING CONTROL RELATED SIGNAL (SYSTEM CHECKING) ..................................3-18
11. MT1389E AUDIO OPTICAL AND COAXIAL OUTPUT (SPDIF)...........................................3-19
12. MT1389E VIDEO OUTPUT WAVEFORM..............................................................................3-19
13. AUDIO OUTPUT FROM MT1389E........................................................................................3-20
CONNECTOR PICTURE...........................................................................................................3-21
1. FULL CONNECTOR PICTURE .............................................................................................3-21
2. CN201 CONNECTOR PICTURE ...........................................................................................3-22
3. CN202 CONNECTOR PICTURE ...........................................................................................3-22
4. CN601 CONNECTOR PICTURE ...........................................................................................3-23
5. CN602 CONNECTOR PICTURE ...........................................................................................3-23
6. CN605 CONNECTOR PICTURE ...........................................................................................3-24
7. CN703 CONNECTOR PICTURE ...........................................................................................3-24
8. CN704 CONNECTOR PICTURE ...........................................................................................3-25
9. P101 CONNECTOR PICTURE..............................................................................................3-25
BLOCK DIAGRAMS...................................................................................................................3-26
1. OVERALL BLOCK DIAGRAM ..............................................................................................3-26
2. POWER SUPPLY BLOCK DIAGRAM...................................................................................3-27
3. SERVO BLOCK DIAGRAM...................................................................................................3-28
4. MPEG & MEMORY BLOCK DIAGRAM ................................................................................3-29
5. VIDEO BLOCK DIAGRAM ....................................................................................................3-30
6. AUDIO BLOCK DIAGRAM....................................................................................................3-31
CIRCUIT DIAGRAMS ................................................................................................................3-33
1. POWER (SMPS) CIRCUIT DIAGRAM ..................................................................................3-33
2. SYSTEM (MPEG) CIRCUIT DIAGRAM.................................................................................3-35
3. SERVO CIRCUIT DIAGRAM.................................................................................................3-37
4. AV/JACK CIRCUIT DIAGRAM ..............................................................................................3-39
5. KARAOKE & USB CIRCUIT DIAGRAM (8 & 9 TOOL)........................................................3-41
6. TIMER/KEY CIRCUIT DIAGRAM (4 & 7 TOOL)...................................................................3-43
7. TIMER/KEY CIRCUIT DIAGRAM (5 TOOL) .........................................................................3-45
8. TIMER/KEY CIRCUIT DIAGRAM (8 TOOL) .........................................................................3-47
9. TIMER/KEY CIRCUIT DIAGRAM (9 TOOL) .........................................................................3-49
• CIRCUIT VOLTAGE CHART ...................................................................................................3-51
PRINTED CIRCUIT DIAGRAMS ............................................................................................3-53
1. MAIN P.C.BOARD .................................................................................................................3-53
2. KEY P.C.BOARD ...................................................................................................................3-55
3. TIMER P.C.BOARD ...............................................................................................................3-55
4. KARAOKE P.C.BOARD (KARAOKE MODEL ONLY) ..........................................................3-56
5. SMPS P.C.BOARD ................................................................................................................3-57
6. SUB SCART (OPTIONAL PART)..........................................................................................3-58
7. SUB 5.1CH (OPTIONAL PART)............................................................................................3-58

3-2
ELECTRICAL TROUBLESHOOTING GUIDE
Is 5.6V present at collector
of Q126?
No 3.3VA
YES
Is 3.3V present at emitter
of Q121?
YES
Is 3.3VA section working?
YES
Is 3.3VA section working?
YES
No 5V No 3.3VA.
Replace Q126. Check FR101 Replace Q121.
YES
Is there a DC voltage at
Cathode of D105 or D107?
YES
NO
NO
NO
NO
Check D105/D106/D107/
D108 and replace.
Replace IC101.
1. POWER CHECK FLOW
A. B.

3-3
Power on
1. 8032 initializes SERVO,DSP & RISC registers
2. Write RISC code to SDRAM
3. Reset RISC
Show LOGO
Tray closed ?
Tray close to closed position
SLED at inner side ?
SLED moves to inner position
1. Judge whether have disc and disc type
2. Jump to related disc reading procedure
Recieve OPEN/CLOSE Key?
1. Execute pressed Key & IR key
2. System operation routine loop
1. Stop playback & open Tray
2. Display tray open message & LOGO
Receive CLOSE Key?
NO
YES
YES
NO
YES
YES
NO
NO
2. SYSTEM OPERATION FLOW

3-4
3. SYSTEM TEST FLOW
TEST
Check the AC Voltage
Power PCBA(110V or 220V) Replace power PCBA or AC transformer.
YES
NO
Switch on the power PCBA
Is the DC voltage outputs OK?
(5V, 3.3V, 12V, 5.6V MOTOR) Repair or Replace Power PCBA
YES
NO
Make sure the main PCBA don't
short on VCCs and switch it on.
YES
Is 3.3V and 1.8V DC outputs
normal on main PCBA? Check the regulators or related diodes.
YES
NO
Connect to PC RS232 cable and
update the FLASH memory code.
Update FLASH successfully? 1. Check 27MHz system clock.
2. Check system reset circuit.
3. Check FLASH R/W enable signal PRD,
RWR.
4. Check RS232 SIGNALS.
5. Check FLASH Memory related circuit.
NO
A
YES

3-5
A
RESET or Power on.
Show LOGO? NO Flash memory
operates properly?
NO
YES
Check connection lines between
FLASH & MT1389E and the FLASH
access time whether is suitable or not.
SDRAM works properly? NO
YES
Check connection lines between
SDRAM & MT1389E and
the SDRAM is damaged.
MT1389E VIDEO
outputs properly?
NO
YES
Check the related
circuit of MT1389E.
Have TV signal output? NO
YES
Check the filtering and amp
circuit of TV signal.
Check AV cable
connection to TV set.
Does tray move inside when
it is not at closed position?
NO Normal TROUT &
TRIN signals?
NO
YES
Check the load OPEN &
CLOSE switch
Normal TRCLOSE &
TROPEN signal?
NO
YES
Check the tray control I/O
pins on MT1389E & IP9008.
Normal LOAD+ &
LOAD-signal?
NO
YES
Check the tray control
amplifying circuit on Motor driver.
B
Check the cable connection
between main PCBA and loader.
YES
YES

3-6
B
Does the SLED move to inner
side when it is at outter position?
NO Motor driver STBY
pin is high?
NO
YES
Check the connection
line of STBY signal.
Is FMSO DC level
higher than 1.4V?
NO
YES
Check the related
circuit of FMSO.
SL+ and SL- output
properly?
NO
YES
Check the amp circuit
on motor driver.
Check the cable
connection with MECHA.
Optical Lens has movements
for searching focus?
Do not put in disc
and tray close.
NO Proper FOSO outputs
to motor driver?
NO
YES
Check FOSO connection on
MT1389E and motor dirver.
Proper F+ & F- outputs? NO
YES
Check the amp circuit
on motor dirver.
CCheck cable connect on
with pick-up head.
YES
YES

3-7
C
Laser turns on when
reading disc?
NO LD01 or LD02 output
properly?
NO
YES
YES
Check the laser power circuit
on MT1389E and connecting
to power transistor.
Collector voltage of
power transistor is OK?
NO Check the related circuit on
laser power transistor.
Check cable connection
between transistor ouput and
pick-up head.
Disc ID is correct?
NO Laser offPut disc in?
NO Proper RFL signal
on MT1389E?
NO
YES
Check the related circuit
on MT1389E RFL signal.
Check LDO1 & LDO2 signal
YES
YES
Does spindle rotate? NO Proper DMSO signal on
MT1389E.
NO
YES
Check DMSO related
circuit on MT1389E.
SP+ & SP- output properly? NO
YES
Check the spindle control
amp circuit of motor driver.
D
Check the cable connection
between spindle and main PCBA.
YES
YES

3-8
D
Focus on OK? NO Proper signals on
A, B, C, D of MT1389E
NO
YES
YES
Check connections between
MT1389E and pick-up head.
Check FEO signal
on MT1389E
NO
Check the FOSO connection
on MT1389E and motor driver.
Check FOSO signal
on MT1389E
Track on OK? NO
NO
Normal TEO Signal
on MT1389E?
NO
YES
Check the related
circuit on MT1389E
YES
YES
YES
T+ & T- output
properly?
NO
YES
Check the tracking control
amp circuit on motor driver.
Properly TRSO signal
on MT1389E?
NO
YES
Check the TRSO
connection on MT1389E
and motor dirver.
Check cable connection
on pick-up head.
Disc is play ? Check RFO & RFLVL
signal waveform.
E

3-9
E
Normal Audio output
when disc playback?
NO Audio DAC received
correct data stream?
NO
YES
YES
Check connection between
MT1389E & audio DAC.
Normal audio DAC out? NO Check the related
circuit of audio DAC.
Check audio filter,
amplify, mute circuit.
Normal IR.VFD & Front
pannel key functions?
NO
NO
Communications between
IR.VFD Front pannel key &
MT1389E is normally?
NO
YES
Check communication
lines on MT1389E.
YES
YES
TEST END Check the cable connection
on Front pannel.