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PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS
CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY, SUBJECT : X-RADIATION
NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFAC- 1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PER-
TURER'S APPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLY SONNEL COVER THE SUBJECT OF X-RADIATION. THE ONLY POTEN-
VOID THE WARRANTY, BUT MAY LEAD TO YOUR BEING LIABLE FOR ANY TIAL SOURCE OF X-RAYS IN CURRENT T.V. RECEIVERS IS THE PIC-
RESULTING PROPERTY DAMAGE OR USER INJURY. TURE TUBE. HOWEVER, THIS TUBE DOES NOT EMIT X-RAYS WHEN
SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE THE HIGH VOLTAGE IS AT THE FACTORY SPECIFIED LEVEL. THE
THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING SAFETY PROPER VALUE IS GIVEN IN THE APPLICABLE SCHEMATIC. OPERA-
CHECKS AND SERVICING GUIDELINES. TO DO OTHERWISE, TION AT HIGHER VOLTAGES MAY CAUSE A FAILURE OF THE PIC-
INCREASES THE RISK OF POTENTIAL HAZARDS AND INJURY TO THE TURE TUBE OR HIGH VOLTAGE SUPPLY AND, UNDER CERTAIN CIR-
USER. CUMSTANCES, MAY PRODUCE RADIATION IN EXCESS OF DESIR-
WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR PROTEC- ABLE LEVELS.
TION FROM A.C. LINE SHOCK. 2. ONLY FACTORY SPECIFIED C.R.T. ANODE CONNECTORS MUST BE
USED. DEGAUSSING SHIELDS ALSO SERVE AS X-RAY SHIELD IN
SAFETY CHECKS COLOR SETS, ALWAYS RE-INSTALL THEM.
AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRCTED. A 3. IT IS ESSNTIAL THAT SERVICE PERSONNEL HAVE AVAILABLE AN
CHECK SHOULD BE MADE OF THE FOLLOWING. ACCURATE AND RELIABLE HIGH VOLTAGE METER. THE CALIBRA
SUBJECT : FIRE & SHOCK HAZARD TION OF THE METER SHOULD BE CHECKED PERIODICALLY
1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN SUCH A WAY AGAINST A REFERENCE STANDARD, SUCH AS THE ONE AVAILABLE
AS TO AVOID POSSIBILITY OF ADJACENT COMPONENT SHORTS. AT YOUR DISTRIBUTOR.
THIS IS ESPECIALLY IMPORTANT ON THOSE MODULES WHICH ARE 4. WHEN THE HIGH VOLTAGE CIRCUITRY IS OPERATING PROPERLY
TRANSPORTED TO AND FROM THE REPAIR SHOP. THERE IS NO POSSIBILITY OF AN X-RADIATION PROBLEM. EVERY
2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE DEVICES TIME A COLOR CHASSIS IS SERVICED. THE BRIGHTNESS SHOULD
SUCH AS INSULATORS, BARRIERS, COVERS, SHIELDS, STRAIN BE RUN UP AND DOWN WHILE MONITORING THE HIGH VOLTAGE
RELIEFS, POWER SUPPLY CORDS, AND OTHER HARDWARE HAVE WITH A METER TO BE CERTAIN THAT THE HIGH VOLTAGE DOES
BEEN REINSTALLED PER ORIGINAL DESIGN. BE SURE THAT THE NOT EXCEED THE SPECIFIED VALUE AND THAT IT IS REGULATING
SAFETY PURPOSE OF THE POLARIZED LINE PLUG HAS NOT BEEN CORRECTLY, WE SUGGEST THAT YOU AND YOUR SERVICE ORGA-
DEFEATED. NIZATION REVIEW TEST PROCEDURES SO THAT VOLTAGE REGU-
LATION IS ALWAYS CHECKED AS A STANDARD SERVICING PROCE-
3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE COLD DURE. AND THAT THE HIGH VOLTAGE READING BE RECORDER ON
SOLDER JOINTS, SOLDER SPLASHES OR SHARP SOLDER POINTS. EACH CUSTOMER'S INVOICE.
BE CERTAIN TO REMOVE ALL LOOSE FOREIGN PARTICLES.
5. WHEN TROUBLESHOOTING AND MAKING TEST MEASUREMENTS IN
4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR DETERIORATION A PRODUCT WITH A PROBLEM OF EXCESSIVE HIGH VOLTAGE,
TO PARTS AND COMPONENTS. FOR FRAYED LEADS, DAMAGED AVOID BEING UNNECESSARILY CLOSE TO THE PICTURE TUBE AND
INSULATION (INCLUDING A.C. CORD). AND REPLACE IF NECESSARY THE HIGH VOLTAGE SUPPLY. DO NOT OPERATE THE PRODUCT
FOLLOW ORIGINAL LAYOUT, LEAD LENGTH AND DRESS. LONGER THAN IS NECESSARY TO LOCATE THE CAUSE OF EXCES
5. NO LEAD OR COMPONENT SHOULD TOUCH A RECIVING TUBE OR SIVE VOLTAGE.
A RESISTOR RATED AT 1 WATT OR MORE. LEAD TENSION AROUND 6. REFER TO HV. B+ AND SHUTDOWN ADJUSTMENT PROCEDURES
PROTRUNING METAL SURFACES MUST BE AVOIDED. DESCRIBED IN THE APPROPRIATE SCHEMATIC AND DIAGRAMS
6. ALL CRITICAL COMPONENTS SUCH AS FUSES, FLAMEPROOF (WHERE USED).
RESISTORS, CAPACITORS, ETC. MUST BE REPLACED WITH EXACT SUBJECT: IMPLOSION
FACTORY TYPES, DO NOT USE REPLACEMENT COMPONENTS
OTHER THAN THOSE SPECIFIED OR MAKE UNRECOMMENDED CIR- 1. ALL DIRECT VIEWED PICTURE TUBES ARE EQUIPPED WITH AN INTE
CUIT MODIFICATIONS. GRAL IMPLOSION PROTECTION SYSTEM, BUT CARE SHOULD BE
TAKEN TO AVOID DAMAGE DURING INSTALLATION, AVOID
7. AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM AN A.C. SCRATCHING THE TUBE. IF SCRATCHED REPLACE IT.
LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OF THE CABI-
NET, (THE CHANNEL SELECTOR KNOB, ANTENNA TERMINALS. HAN- 2. USE ONLY RECOMMENDED FACTORY REPLACEMENT TUBES.
DLE AND SCREWS) TO BE SURE THE SET IS SAFE TO OPERATE SUBJECT : TIPS ON PROPER INSTALLATION
WITHOUT DANGER OF ELECTRICAL SHOCK. DO NOT USE A LINE 1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS, CUBBY-
ISOLATION TRANSFORMER DURING THIS TEST USE AN A.C. VOLT- HOLE OR CLOSELY FITTING SHELF SPACE. OVER OR CLOSE TO
METER, HAVING 5000 OHMS PER VOLT OR MORE SENSITIVITY, IN HEAT DUCT, OR IN THE PATH OF HEATED AIR FLOW.
THE FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT RESIS-
TOR, PARALLELED BY A .15 MFD. 150.V A.C TYPE CAPACITOR 2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIO
BETWEEN A KNOWN GOOD EARTH GROUND (WATER PIPE, CON- INSTALLATIONS WHERE DEW IS A FACTOR, NEAR STEAM RADIA-
DUIT, ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME. TORS WHERE STEAM LEAKAGE IS A FACTOR, ETC.
MEASURE THE A.C. VOLTAGE ACROSS THE COMBINATION OF 1500 3. AVOID PALCEMENT WHERE DRAPERIES MAY OBSTRUCT REAR
OHM RESISTOR AND .15 MFD CAPACITOR. REVERSE THE A.C. PLUG VENTING. THE CUSTOMER SHOULD ALSO AVOID THE USE OF DEC-
AND REPEAT A.C. VOLTAGE MEASUREMENTS FOR EACH EXPOSED ORATIVE SCARVES OR OTHER COVERINGS WHICH MIGHT
METALLIC PART. VOLTAGE MEASURED MUST NOT EXCEED 75 OBSTRUCT VENTILATION.
VOLTS R.M.S. THIS CORRESPONDS TO 0.5 MILLIAMP A.C ANY
4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMER-
VALUE EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL SHOCK
CIAL MOUNTING KIT. MUST FOLLOW THE FACTORY APPROVED
HAZARD AND MUST BE CORRECTED IMMEDIATELY.
MOUNTING INSTRUCTIONS A PRODUCT MOUNTED TO A SHELF OR
A.C. VOLTMETER 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.
GOOD EARTH GROUND PLACE THIS PROBE 6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE ON ITS
SUCH AS THE WATER ON EACH EXPOSED MOUNTING TO THE CART. CAUTION THE CUSTOMER ON THE HAZ-
PIPE. CONDUIT. ETC METAL PART 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
SUBJECT: GRAPHIC SYMBOLS WHICH HAS NOT BEEN LISTED BY UNDERWRITERS LABORATORIES,
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN INC. FOR USE WITH THEIR SPECIFIC MODEL OF TELEVISION
AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE RECEIVER OR GENERICALLY APPROVED FOR USE WITH T.V.'S OF
SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED THE SAME OR LARGER SCREEN SIZE.
"DANGEROUS VOLTAGE" THAT MAY BE OF SUFFICIENT MAG-
8. CAUTION CUSTOMERS AGAINST THE USE OF EXTENSION CORDS,
NITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK.
EXPLAIN THAT A FOREST OF EXTENSIONS SPROUTING FROM A SIN-
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIAN- GLE OUTLET CAN LEAD TO DISASTROUS CONSEQUENCES TO
GLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO HOME AND FAMILY.
THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN
SERVICE LITERATURE.
1-3
SERVICING PRECAUTIONS
CAUTION : Before servicing the DVD player covered by this Electrostatically Sensitive (ES) Devices
service data and its supplements and addends, read and fol- Some semiconductor (solid state) devices can be damaged
low the SAFETY PRECAUTIONS. NOTE : if unforeseen cir- easily by static electricity. Such components commonly are
cumstances create conflict between the following servicing called Electrostatically Sensitive (ES) Devices. Examples of
precautions and any of the safety precautions in this publi- typical ES devices are integrated circuits and some field
cations, always follow the safety precautions. effect transistors and semiconductor chip components.
Remembers Safety First: The following techniques should be used to help reduce the
incidence of component damage caused by static electricity.
General Servicing Precautions
1. Always unplug the DVD player AC power cord from the AC 1. Immediately before handling any semiconductor compo-
power source before: nent or semiconductor-equipped assembly, drain off any
(1) Removing or reinstalling any component, circuit board, electrostatic charge on your body by touching a known
module, or any other assembly. earth ground. Alternatively, obtain and wear a commer-
(2) Disconnection or reconnecting any internal electrical cially available discharging wrist strap device, which
plug or other electrical connection. should be removed for potential shock reasons prior to
(3) Connecting a test substitute in parallel with an elec- applying power to the unit under test.
trolytic capacitor.
Caution : A wrong part substitution or incorrect 2. After removing an electrical assembly equipped with ES
polarity installation of electrolytic capacitors may result devices, place the assembly on a conductive surface such
in an explosion hazard. as aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
2. Do not spray chemicals on or near this DVD player or any
of its assemblies. 3. Use only a grounded-tip soldering iron to solder or
unsolder ES devices.
3. Unless specified otherwise in this service data, clean
electrical contacts by applying an appropriate contact 4. Use only an anti-static solder removal device. Some
cleaning solution to the contacts with a pipe cleaner, solder removal devices not classified a "anti-static" can
cotton-tipped swab, or comparable soft applicator. generate electrical charges sufficient to damage ES
Unless specified otherwise in this service data, lubrication devices.
of contacts is not required.
5. Do not use freon-propelled chemicals. These can
4. Do not defeat any plug/socket B+ voltage interlocks with generate electrical charge sufficient to damage ES
whitch instruments covered by this service manual might devices.
be equipped.
6. Do not remove a replacement ES device from its protec
5. Do not apply AC power to this DVD player and/or any of tive package until immediately before you are ready to
i t s install it. (Most replacement ES devices are packaged with
electrical assemblies unless all solid-state device heat leads electrically shorted together by conductive foam,
sinks are cerrectly installed. aluminum foil, or comparable conductive material).
6. Always connect test instrument ground lead to the
appropriate ground before connection the test instrument 7. Immediately before removing the protective material from
positive lead. Always remove the test instrument ground the leads of a replacement ES device, touch the protective
lead last. material to the chassis or circuit assembly into which the
device will be installed.
Insulation Checking Procedure
Disconnect the attachment plug from the AC outlet and turn Caution : Be sure no power is applied to the chassis or
the power on. Connect an insulation resistance meter(500V) circuit, and observe all other safety precautions.
to the blades of the attachment plug. The insulation resis-
tance between each blade of the attachment plug and acces- 8. Minimize bodily motions when handling unpackaged
sible conductive parts (Note 1) should be more than 1M- replacement ES devices. (Normally harmless motion such
ohm. as the brushing together of your clothes fabric or the lifting
Note 1 : Accessible Conductive Parts including Metal pan- of your foot from a carpeted floor can generate static elec-
els, Input terminals, Earphone jacks, etc. tricity sufficient to damage an ES device.)
1-4
SPECIFICATIONS
DVD VIDEO PLAYER
Power supply 100~240V, 50/60Hz
Power consumtion 20W
Mass 3.5kg(7.7lbs)
External dimensions 430 x 80 x 298 (W x H x D)
Signal system NTSC
Laser Semiconductor laser, wavelength 655nm(DVD)/795nm(CD)
Frequency range (digital audio) 2Hz to 44kHz
Signal-to-noise ratio (digital audio) More than 105dB (EIAJ)
Audio dynamic range (digital audio) More than 95dB (EIAJ)
Harmonic distortion(digital audio) 0.003%
Wow and flutter Below measurable level (less than +0.001%(W.PEAK)) (EIAJ)
Operations Temperature : 5°C(41°F) to 35°C(95°F),
Operation status : Horizontal
OUTPUTS
Video outputs 1.0V(p-p), 75, negative sync., RCA jack x 1
S video outputs (Y)1.0V(p-p), 75, negative sync.,Mini DIN 4-pin x 1
(C)0.286V(p-p), 75
Component video output (Y)1.0V(p-p), 75,negative sync., RCA jack x 1
(Pb)/(Pr) 0.7V(p-p), 75
Audio output(digital audio) 0.5V(p-p), 75, RCA jack X 1
Audio output(optical audio) Optical connector x 1
Audio output(analog audio) 2.0Vrms (1kHz, 0dB), 330, RCA jack (L, R) x 1
*Designs and specifications are subject to change without notice.
*Weight and dimensions shown are approximate.
1-5
LOCATION OF CUSTOMER CONTROLS
F R O N T PA N E L
1 2 3 4 5 6
slow/scan
power open/close pause/step menu select/enter
fw
rev
d
play stop skip
12 11 10 9 8 7
R E A R PA N E L
1 2 3 4
DOLBY DIGITAL 5.1CH COMPONENT AUDIO
FRONT REAR VIDEO OUT OUT
L
Pb L
R
DIGITAL OUT S-VIDEO
Pr R
OUT
COAXIAL CENTER WOOFER Y VIDEO
OUT
OPTICAL
8 7 6 5
F R O N T PA N E L R E A R PA N E L
11. POWER/STANDBY BUTTON AND INDICATOR 1. COAXIAL DIGITAL AUDIO OUT JACK
12. DISPLAY WINDOW 2. COMPONENT VIDEO OUT JACKS
13. PAUSE/STEP BUTTON 3. AUDIO OUT(R/L) JACKS
14. MENU BUTTON 4. POWER CORD
15. SELECT/ENTER BUTTON 5. S-VIDEO OUT JACK
16. SHUTTLE RING 6. VIDEO OUT JACK
17. ARROW BUTTONS 7. DOLBY DIGITAL AUDIO OUT JACKS
18. SKIP BUTTONS 8. OPTICAL DIGITAL AUDIO OUT JACKS
19. STOP BUTTON
10. PLAY BUTTON
11. DISK TRAY
12. OPEN/CLOSE BUTTON
1-6
Display Window
1 2 3 4 5
9 8 7 6
1. Title number indicator 6. Total playing time
2. DVD indicator 6. /elapsed time indicator
3. CD indicator 7. Operating status indicator
4. Repeat playback mode indicators 8. Angle icon indicator
5. RANDOM indicator 9. Chapter/Track number indicator
REMOTE CONTROL
POWER button DVD/VCR/CATV/TV
Selector Switch
PLAY button
REV SKIP button FWD button
STOP button
PAUSE/STEP button
SELECT/ENTER button OPEN/CLOSE button
RESUME button **ARROW(Volume/Channel) buttons
DISPLAY button RETURN(TV INPUT) button
NUMBER button SOUND(MUTE) button
PROGRAM button
CLEAR button
ANGLE button *MENU button
SUBTITLE button ***TITLE buttons
MARKER-SEARCH button
AUDIO button ZOOM button
SETUP button RANDOM button
A-B button
REPEAT button
FWD/REV SLOW/SCAN
Shuttle Ring
*MENU button
Use the MENU button to display the menu screen
included on DVD video discs. To operate a menu
screen, follow the instructions in "Using a DVD
Menu".
***TITLE button
Use the TITLE button to display the title screen **Directional arrow buttons
included on DVD video discs. To operate a menu (up, down, left, right) for use in highlighting a selection
screen, follow the instructions in "Using a Title Menu". on a GUI menu screen, TITLE and MENU screen.
1-7
DISASSEMBLY
CAUTION BEFORE STARTING SERVICING
Electronic parts are susceptible to static electricity and may easily damaged, so do not forget to take a
proper grounding treatment as required.
Many screws are used inside the unit. To prevent missing, dropping, etc. of the screws, always use a
magnetized screw driver in servicing. Several kinds of screws are used and some of them need special
cautions. That is, take care of the tapping screws securing molded patrs and fine pitch screws used to secure
metal parts. If they are used improperly, the screw holes will be easily damaged and the parts can not be fixed.
CABINET DISASSEMBLY 3. Front Panel
1. Top Case 1. Eject the disc tray. (See Fig. 2-2)
1. Release 7 screws (A). (See Fig. 2-1) 2. Remove the tray door. (See Fig. 2-2)
2. Lift the top case with holding the back of it, 3. Release 2 screws (B).
and remove it in the direction of the arrow 4. Pull the front panel toward you while pressing
7 stoppers to disengage, and remove the front
Top Case (A) (A) panel. (See Fig. 2-3)
(A)
(A)
(A)
(A)
(A)
(B)
(B)
Stopper
Stopper
Front Panel
Fig. 2-1
Fig. 2-3
2. Tray Door
1.Eject the disc tray.
2.Lift up the tray door in the direction of the
arrow.
Tray Door
Disc Tray
Fig. 2-2
2-2
CIRCUIT BOARD DISASSEMBLY
Note: 3. Digitron and Key Circuit Board
Before removing the main circuit board, be sure to 1. Remove the front panel.(See Fig. 2-3)
shortcircuit the laserdiode output land. 2. Release 8 screws(E), and remove the digitron
After replacing the main circuit board, open the land circuit board.
after inserting the flexible connector.
(Refer to Mechanism Disassembly)
1. Main/A/V Circuit Board Key
Circuit Board
1. Remove the top case.(See Fig.2-1)
(E)
2. Release 10 screws (C), and take out the main / (E)
AV circuit board.(See Fig.2-4)
(E)
3. Remove the flexible connectors and the
connector from main circuit board. (E)
(E)
4. Then, remove the main A/V circuit board.
(E)
(C)
(C)
Digitron
A/V Circuit Board (C) Circuit Board
(C)
(C)
(C)
Fig. 2-6
Main Circuit Board Flexible
connector
Flexible
connector
(C)
(C)
(C)
(C)
Fig. 2-4
2. Power Circuit Board
1. Relrase 4 screws(D). (See Fig. 2-5)
Power Code
(D)
(D)
(D)
(D)
Power
Circuit
Board
Fig. 2-5
2-3
1
2
3
4
5
1. Cabinet and Main Frame Section
463 PBJ00
A
250
462
462
462
260
A00
EXPLODED VIEWS
462
B
452
462
2-4
452
PB 283 463
K0
0
463 PB 463
T0 452
0
300
463
455
A47
463 463
C
463
A48
280 PB 463
S0
0 A46
A43
277
278
D
2.Packing Accessory Section
806 CABLE
808 BATTERY 811
812
900 REMOCON 813
801 OWNER'S MANUAL
804 PACKING SHEET
803 PACKING
803 PACKING
802 BOX CARTONX
3.Remote Control Section
906 909
905
902 903
904
908 907
901
900
2-5
ELECTRICAL TROUBLESHOOTING GUIDE
1. Power Circuit
· Input Voltage : 90V - 135V
· It is possible to malfunction, if the unload condition is left for a long time when power is on.
(More than Dummy load 100mA)
· A Primary side is abnormal when the fuse is short, secondary side is abnormal when the IC103 oscillates
intermittently.
· The resistor value of both terminal is measured with DVM crossing each other to check the each element is
normal or abnormal. (It is normal when the numerical value is different each other.)
START
NO NO
Is F901 normal? Is voltage of BD901 140V?
A primary side is abnormal.
Check the GND of C901 and
YES YES
IC901 Pin 3 with oscilloscope.
NO Is IC901 Pin 3 NO Is IC905 Are R907, D902, NO
switching normally? normal? D903 and R902
When IC901 normal?
oscillating In condition of DC140V. YES
YES YES
(Feedback is abnormal)
Does oscillate Check or
NO Are D901, R904, NO
continuously when
Is CN903 Pin 3 5.2V? replace R905 and R906
the CON903 is
D908. normal?
disconnected ?
YES Secondary side YES YES
Front Circuit is abnormal.
Board is After connect Are R922, C927, NO NO
abnormal CON903 R921 and R918 Is PC901 normal?
Pin 1 , 3 short. normal?
Are D908, D909, YES
D907, D910, D906 (A)
and D905 normal? END
NO Are CON902
YES
Pin 5 , 6 and 9 5V?
Replace Q908
YES
and Q909.
Replace defective
parts.
NO Is CON903 Pin 3 NO
Is CON904 Pin 3 8V?
5.2V?
YES YES
Replace
IC902.
NO
Is CON902 Pin 3 12V?
Check Q904 YES
Replace To (A).
and ZD903.
defective
parts.
Are CON903 Pin 5
-24V, Pin 7 -20V and
Pin 8 -16V? NO
YES
(Fig. 3-1) IC901 Pin 3
Normal switching waveform on the
END stand-by mode at the AC110V
3-2
2. µ-COM Circuit
A. No Power
POWER ON
NO
Power RED LED on? Refer to Front Part.
YES
NO
Does Bar appear at FLD?
YES NO Is CON107 YES
Do all five Bars appear? connected normally?
NO
Reconnect it.
Does Logo appear NO Check power.
on the screen? (Refer to power)
YES If power is
normal
OK
NO
Is CON107 Pin6 normal?
Refer to Front Part YES
1
A 1
NO The
Is oscillation of NO waveform on A[00:21]
Check the oscillation
X101 normal? and D[00:15] of IC108
normal?
YES YES
Check short
Are IC107 Pin 14 , 28 NO
Check short. NO
and 29 normal? Are IC101 Pin 7 , 8 normal?
OK
YES
YES
Replace IC107 Replace IC101.
A or IC108.
Replace Main B/D.
3-3
B. Audio abnormal C. Video abnormal
AUDIO ABNORMAL VIDEO ABNORMAL
Check Audio jack. Check Video jack.
YES (If OK) YES (If OK)
Check PLL FC of MPEG part. Refer to Video part.
YES (If OK) YES (If OK)
Refer to Audio part. Refer to Encoder part.
YES (If OK) YES (If OK)
Refer to MPEG part. Refer to MPEG part.
YES (If OK) YES (If OK)
Replace B/D. Replace B/D.
D. Open/Close abnormal
OPEN/CLOSE ABNORMAL
Check Front.
YES (If OK)
Check the NO
connection of CON107. Reconnect it.
YES
NO
Check the connection of MD. Check IC101 Pin 13 , 14.
YES YES
Refer to SERVO part.
3-4
E. Picture abnormal
PICTURE ABNORMAL
Check the disc.
Refer to Servo part
If OK
Check PLL IC of MPEG part
YES (If OK)
Check DSP
YES (If OK)
Check MPEG
YES (If OK)
Replace B/D
F. Disc Error
DISC ERROR
Check Disc
YES (If OK)
Refer to Servo part
YES (If OK)
Replace B/D
3-5
3. MPEG Circuit
Power is on
Does LG Logo appear NO
Check power & clock. A
on the screen?
YES
YES
Does the
moving picture of the DVD Disc NO NO Check CD/DVD DSP output
Is MPEG data signal normal? B
play on the screen signal.
normally?
OK
YES YES OK
Check MPEG Decoder input
C
signal.
YES NO Check CD/DVD DSP output
Is error signal normal? D
signal.
OK
Check MPEG Decoder input
E
signal.
Does the
moving picture of the video NO NO
Is MPEG data signal normal? Check CD/DVD DSP output
CD play on the screen F
signal.
normally?
YES YES OK
_ OPTION
_ If included VCD function. Check MPEG Decoder input
G
signal.
NO
Is Clock normal?
Check clock signal H
YES
NO Does the audio
Does the audio sound sound output from MPEG Check clock signal
output normally? decoder? I
YES YES
END
3-6
4. Front Circuit (Digitron & key)
START
Power on.
NO Is oscillation of NO
LED ON? X501 normal? Check Power.
YES YES
NO Check waveform NO
Is Digitron on normally? Replace IC501.
of IC500 Pin 6 .
YES CD YES
Do all the NO NO NO
buttons work Is waveform of IC500 Check waveform
normally? Pin78 normal? of IC500 Pin13 .
YES YES YES Solder Key part.
Check waveform of NO
Replace IC500.
IC500 Pin13 .
YES
Check waveform NO
Solder defective parts again
of Q500 Pin 2 .
YES Replace Q500.
Check and replace R516,
R507, R506, R500, R505, Replace LED501.
R504, R512 and R503.
NO Does pulse NO NO
Does remote control waveform of RE500 Pin 3 Is RE500 Pin 2 5V? Solder defective parts
work normally? appear?
YES YES YES
Is IC500
Pin24 connected to Replace RE500
RE500 Pin 3 ?
YES
YES
Complete repairing Front B/D. Replace IC500. Re-solder.
YES YES Recheck
3-7
5. RF/Servo Circuit
A.
CHECK POINT(General)
Does signal goes NO
"High" to IC206 Pin194 when the
power is on?
YES
Does signal pulse NO
input to IC206 Pin 58 , 59 when Check "2.µ-COM Part".
the powe is on?
YES
Does Does
TTL pulse output to NO 33.8688MHz clock input NO Replace X301 or
IC206 Pin14, 14? to IC206 Pin 63? IC308(30MHz clock defect)
YES YES
Replace IC206
(IC206 soldering or IC defect).
Is IC206 NO Replace IC700
Pin83, 84, 88, 89 voltage (IC700 soldering or IC defect)
about 2.2V?
YES
END
3-8
B.
No disc
Power on Check loading Part.
NO Push Pick-up to inner track to
Does tray open or close?
the end by hand.
YES
Does
CON202 Pin17 change NO DECK assembly is defective.
high to low? (Limit sw)
YES
Pressing
the open/close key NO
repeatedly, check the voltage of check µ-COM Part.
CON202 Pin 9 change
0V to 5V
YES
Junction Board
Does
the voltage change NO
at IC401 Pin 15 , 16 more than Replace IC401.
2V on the basis of
4.5V?
YES
DECK assembly is defective.
Fig.1. SLED Driver waveform
Does the pick-up NO Check SLED Driver output. IC206 Pin 88 no output : IC206 is defective
slide inner or outer IC206 Pin 88 IC401 Pins 18 ,17. IC401 Pin 18 no output : IC401 is defective
track?
YES
Fig.2. Focus Driver waveform
Does
the pick-up lens move up NO Check Focus Driver output. IC206 Pin 83 no output : IC700 is defective
and down? (IC206 Pin 83, IC401 Pins 11,12) IC401 Pin 1 , 2 no output : IC701 is defective
YES
Slide the pick-up to
inner track.
END
3-9
C.
DISC IN
OPEN/CLOSE
Fig.3. FOCUS ERROR waveform
Check
NO the focus error moving the NO Check IC201 Pin 52 , 53 , 54 , 55 in DVD Mode
FOCUS ON? lens up and down. Check IC201 Pin 58 , 59 , 60 , 61 in CD Mode
(IC201 Pin 21)
YES YES IC201 no output : Pick-up is defective.
Does the NO
TTL level change at IC206
Pin 78 and 13 moving Replace IC206.
the lens?
YES
Replace µ-COM or IC206.
NO Check CON404 Pin4, 6 Motor
Does the disc turn? Check IC206 and IC403 when the Pin 4 is abnormal
turn when the Pin4 is less than 1.6V
YES
NO
IC206 Pin16 is "High"? Check A
YES
NO Does the signal NO µ-COM part is
Is OK the track jump. pulse input at IC700 Pin 27, defective. Check
28 , and 29?
"2.µ-COM Circuit."
YES YES
NO Video Par is defective.
Does the screen appear? Check "5.MPEG Circuit." Replace IC700.
Check "7.OSD/Video Circuit."
YES
END
3-10
D.
CHECK A
Fig.5. RF
waveform
Check RF Eye-Pattern. NO
Check IC201 Pin 52 , 53 , 54 , 55 in DVD Mode.
Check IC201 Pin 58 , 59 , 60 , 61 in CD Mode.
No signal: Pick-up is defective
RF : 1.0-2.1V(IC201 Pin 28)
YES
NO Does the NO NO
Is the eye-pattern vivid? sawtooth waveform emit Does the 1.6V emit? Replace IC201.
at IC201 Pin 20 ?
YES YES YES
Replace IC206. Check IC206 Pin84.
No signal at IC206 : IC206 is defective
· Check IC206 Pin 162
· Both are normal : IC206 is defective
· Check the clock at the IC206 Pin 28, 30 .
END
3-11
1. Overall Block Diagram
BLOCK DIAGRAMS
DISC
DVD_LDQM, DVD_SD_CS1
RFRP, RFCen, IC307
TE, Vref GM72V1621 DVD_MA[0:11]
Comp. DRAM
DVD : A, B, C, D 1M x 16bit
IC201 256K x 16bit DVD_MD[0:15]
DVD : RF SDRAM
TA1254F
CD : A, B, E, F FE, TE, RFRP, SBADD, DVD/CD RF
PICK RF SIGNAL
SPINDLE
ICDATA[00:15]
M PROCESSOR TEBAL, FEBAL, DVD_SD_CAS,
ICADDR[0:8]
MOTOR UP
DPOCTL, EQF, EQB DVD_SD_RAS
IC306 DVD_SD_CLK