NAD L55 User manual

SERVICE MANUAL
L55
DVD/VIDEO CD/CD
PLAYER
DVD/VIDEO CD/CD PLAYER
L55

1-2

1-3
PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO 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
CORRECTED. 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 RECEIVING
TUBE OR A RESISTOR RATED AT 1 WATT OR MORE. LEAD
TENSION AROUND PROTRUDING 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 SAFETY 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 MEASURE 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
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 PLACEMENT 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
COMMERCAL 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.
THE LIGHTNING FLASH WITH ARROWHEAD SYMBOL, WITHIN AN
EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE USER TO THE
PRESENCE OF UNINSULATED “DANGEROUS VOLTAGE” WITHIN THE
PRODUCT’S ENCLOSURE 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 USER TO THE PRESENCE OF IMPORTANT
OPERATING AND MAINTENANCE (SERVICING) INSTRUCTIONS IN THE
LITERATURE ACCOMPANYING THE APPLIANCE.
A.C. VOLTMETER
PLACE THIS PROBE
ON EACH EXPOSED
METAL PART
GOOD EARTH GROUND
SUCH AS THE WATER
PIPE. CONDUIT. ETC 10 WATT
1500 OHM
0.15uF

1-4
SERVICING PRECAUTIONS
CAUTION : Before servicing the DVD player 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 publication, always follow the safety precautions.
Remember Safety First:
General Servicing Precautions
1. Always unplug the DVD player's AC power cord from the AC
power source before:
(1) Removing or reinstalling any component, circuit board,
module, or any other assembly.
(2)Disconnecting 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 player 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, cottontipped 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 which
instruments covered by this service manual might be equipped.
5. Do not apply AC power to this DVD player and/or any of its
electrical assemblies unless all solid-state device heat sinks are
correctly installed.
6. Always connect test instrument ground lead to the appropriate
ground before connecting 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 1M-ohm.
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 grounded-tip soldering iron to solder or unsolder ES
devices.
4. Use only an antistatic 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 freonpropelled 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. lmmediately 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 handing 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
DVD player/Outputs/Supplied Accessories
[DVD player]
[Outputs]
[Supplied
Accessories]
Power supply AC 230V / 50 Hz (EUROPE), AC 110V/60Hz (USA / CANADA)
Power consumption 15 W
Mass 3.3 kg
External dimensions (W X H X D) 285 x 103x 291 mm
Signal system PAL (EUR) , NTSC (USA / CANADA)
Laser Semiconductor laser, wavelength 650 nm
Frequency range (audio) 4 Hz to 20 kHz
Signal-to-noise ratio (audio) More than 100 dB (EIAJ)
Dynamic range (audio) More than 95 dB (EIAJ)
Harmonic distortion (audio) 0.008 %
Wow and flutter
Below measurable level (less than + 0.001 % (W.PEAK)) (EIAJ)
Operating conditions Temperature: 41°F to 95°F, Operation status: Horizontal
Video output 1.0 V (p-p), 75 , negative sync., RCA jack x 1
S-video output (Y) 1.0 V (p-p), 75 , negative sync., Mini DIN 4-pin x 1
(C) 0.286 V (p-p), 75 ,
SCART video output CVBS 1.0 V (p-p), 75 , negative sync., RCA jack x 1
(RGB) 0.63 V (p-p), 75
Audio output (digital audio) 0.5 V (p-p), 75 , RCA jack x 1
Audio output (optical audio) Optical connector x 1
Audio output (analog audio) 2.0 Vrms(1 KHz, 0 dB), 330 , RCA jack (L, R) x 1
Video cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Audio cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
*Designs and specifications are subject to change without notice.

1-6
Front Panel
Display Window
POWER indicator
(Standby mode: Blue color)
POWER button
REMOTE SENSOR DISPLAY WINDOW
OPEN/CLOSE button
SKIP/SCAN buttons
Disc tray PLAY button
PAUSE/STEP button
STOP button
OPERATING STATUS indicator
CD indicator
VCD indicator DVD indicator PROGRAM indicator
Repeat playback
mode indicators
CHP/TRK NUMBER indicator
TOTAL PLAYING
TIME/ELAPSED TIME
indicator
TITLE NUMBER indicator
ANGLE ICON indicator
REMOTE
CONTROL
SUB
WOOFER
CENTER
VIDEO OUT
REAR
OPTICAL COAXIAL
FRONT
5.1 CH OUTPUT
DIGITAL OUT
S-VIDEO OUT EURO AV-TV-VCR
AUDIO
OUT
SYSTEM SINGLE
REMOTE CONTROL
SELECTOR

1-7
Rear Panel
COMPOSITE VIDEO OUT jack
COMPOSITE VIDEO OUT jack
COMPONENT VIDEO OUT jack
MIXED AUDIO OUT jacks
MIXED AUDIO OUT jacks
EURO AV-TV-VCR OUT jack
OPTICAL DIGITAL AUDIO OUT jack
DIGITAL AUDIO OUT jacks
(COAXIAL)
DIGITAL AUDIO OUT jacks
(COAXIAL)
POWER CORD
Connect to an AC 230V, 50Hz
outlet only.
POWER CORD
Connect to an AC 110V, 60Hz
outlet only.
S-VIDEO OUT jack
S-VIDEO OUT jack
*EUR VERSION
*USA/CANADA VERSION
OPTICAL DIGITAL AUDIO OUT jack

REMOTE CONTROL
****REMOTE SELECT
1-8

BJA2B043Z
KOP11408B
KOP11401CSMPS
10
1
KGX1A304
SHEET
KUP11408C
x11
S1
x4
S3
x4
S10
x3
x5
x2
S6
S7
19
12 x4
S6 x4
13 x4
x2
S5
S5 x4
20
x2
S4
14
S9
S10
25
26
X2
18
17
X2
23
16
24
S6
X2
S5
S6
S7
22
21
11
S11
27
15
S4
x2
S2
4
28
x2
9
8
6
S2
7
5
3
2
4
1
1
1
BKL1A060
BHG1A171
FOOT CUSHION
FOOT
1
KKF1A210Z
REAR PANEL
KUP11390Z
AV PCB ASS'Y
1
POWER PCB ASS'Y
1
KMD1A420
PCB BRACKET
1
BVNTFCEIE311A
MAIN PCB ASS'Y
1
KHR1A028
AC CORD BUSHING
1
AC CORD
KBT1A745M7K102
KBT1A746M7K102
KGU1A245A10
KGL1A188
KKM1A051C26
KGU1A244A8
2KTB4+6JFZ
S11 SCREW
9
KTB3+6JFZ
S10 SCREW
KHE170
PCB HOLDER
2
DISPLAY KNOB
1
POWER KNOB
1
SENSOR WINDOW
1
QT`Y
1
2
1
0.17
KKM1A106ZC26
KGR1A214M7ZK102
PARTS-NO
SIDE BAR
NO
1
4
3
x2
6
5
S6
2
8
7
11
10
9
13
12
14
15
DESCRIPTION
FRONT PANEL
DOOR ORNAMENT
FIP WINDOW
LED INDICATOR
4
4
1
1
2
1
1
1
1
KUA1A189
BJDTVM502/1
KGW1A298
KKC3B076S33
KHG1A104
KMD1A413
1
FRONT PCB ASS'Y
18
17
19
20
22
25
24
23
21
27
26
29
28
QT`Y
4
4
4
6
9
KTB3+10G
KHD1A016
KTB3+6J
KTS3+8J
KTB3+6F
PARTS-NO
3
2
2
KTW3+12J
KTB3+8J
KTB3+10GFZ
KTW3+8J 12
PCB BRACKET
SUB PANEL
TOP CABINET
CUSHION
BOTTOM CHASSIS
MECHANISM,DVD
JACK,BOARD
16
1
MECHA. SUPPORT KMH1A113
X2
SCREW
SCREW,SPECIAL
SCREW
SCREW
SCREW
NO
S3
S2
S5
S4
S1
SCREW
SCREW
SCREW
S7
S9
S8
S6 SCREW
DESCRIPTION
EXPLODED VIEW
1-9 1-10

2-1
SECTION 2
ELECTRICAL
CONTENTS
ELECTRICAL TROUBLESHOOTING GUIDE......................................................................2-2
1. Power (SMPS) Circuit ..............................................................................................................2-2
............................................................................................................................2-3
3. MPEG Circuit............................................................................................................................2-6
4. Front Circuit (Digitron & Key) ...............................................................................................2-7
5. RF/Servo Circuit ......................................................................................................................2-8
BLOCK DIAGRAMS ..................................................................................................................2-12
1. Overall Block Diagram ..........................................................................................................2-12
2. Power (SMPS) Block Diagram..............................................................................................2-13
3. RF/CD DSP/DVD DSP/DVD servo Block Diagram ..............................................................2-14
4. Audio Block Diagram ............................................................................................................2-15
5. MPEG Block Diagram...........................................................................................................2-16
...........................................................................................................2-17
CIRCUIT DIAGRAMS................................................................................................................2-18
1. Power (SMPS) Circuit Diagram ............................................................................................2-18
2. DVD DSP Circuit Diagram.....................................................................................................2-20
3. Drive & RF Circuit Diagram ..................................................................................................2-22
4. MPEG Circuit Diagram ..........................................................................................................2-24
4-1. WAVEFORMS ...................................................................................................................2-26
5. Audio DM & 5.1CH Circuit Diagram .....................................................................................2-28
....................................................................................................................2-30
7. DIGITRON & Key Circuit Diagram ........................................................................................2-32
8. Jack Circuit Diagram .............................................................................................................2-34
PRINTED CIRCUIT DIAGRAMS ............................................................................................2-36
1. MAIN P.C.BOARD ...................................................................................................................2-36
2. POWER P.C.BOARD..............................................................................................................2-38
3. AV P.C.BOARD.......................................................................................................................2-40
4. FRONT P.C.BOARD ...............................................................................................................2-42

2-2
Is 5.2V applied
to CN62 Pin 5 ? Check FRONT Circuit
Check L620, R620
No LED
Check R622, R623
Check D601-D604
Check Q626, D609
Check IC64, D628, D621
Check Q622, Q623, R632
Check Q620, Q625, R625
No 8V No 3.3V
Check D625, IC62
Check IC67, R609
NO FLD
1. POWER (SMPS) Circuit
ELECTRICAL TROUBLESHOOTING GUIDE
END
No 5V_D, 5V_A
NO
NO
NO
NO
YES
YES
YES
YES
Is High State applied
to CN63 Pin 2 ?
Is 5.2V applied
to PT61 Pin 1 ?
Is -24V applied
to CN62 Pin 3 ?

2-3
Is LED On? Is CN61 conneted
correctly?
Check L620, R620 Check Power Circuit
Check the oscillation
Check short
Replace IC501 or IC503
AC In
Power On Reconnect CN61
OK
Replace Main B/D
2. u-COM Circuit
A. NO Power
NO
Check FRONT Circuit
NO
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
Is LED Off ?
Does bar appear
on FLD ?
Is oscillation of
X501 normal?
Are IC503 Pin 14, 28
and 29 normal?
Are IC506 Pin 7, 8
normal?
The waveform on
A[00:21] and D[00:15] of
IC501 normal?
Does logo appear
on the screen?
Is 5.2V applied
to CN61 Pin 12 ?

2-4
B. Audio abnormal
D. Open/Close abnormal
Check the
connection of P5901.
Check IC501 Pins 13, 14.
Check Audio jack.
YES (If OK)
YES
NO
NO
YES
YES (If OK)
YES
YES (If OK)
YES (If OK)
YES (If OK)
Check PLL FC of MPEG part.
Refer to Audio part.
Refer to MPEG part.
Replace B/D.
Check Front.
Reconnect it.
Refer to SERVO part.
Check the connection of MD.
AUDIO ABNORMAL
OPEN/CLOSE ABNORMAL
C. Video abnormal
Check Video jack.
YES (If OK)
YES (If OK)
YES (If OK)
YES (If OK)
Refer to Video part.
Refer to Encoder part.
Refer to MPEG part.
Replace B/D.
VIDEO ABNORMAL

2-5
E. Picture abnormal
Check the disc.
If OK
YES (If OK)
YES (If OK)
Refer to Servo part
Check PLL IC of MPEG part
Check DSP
Check MPEG
YES (If OK)
Replace B/D
PICTURE ABNORMAL
F. Disc Error
Check Disc
YES (If OK)
YES (If OK)
Refer to Servo part
Replace B/D
DISC ERROR

2-6
Power is on
Does LG Logo appear
on the screen?
Does the
moving picture of the DVD Disc
play on the screen
normally?
Is MPEG data signal normal?
Is error signal normal?
Is MPEG data signal normal?
Is Clock normal?
Does the audio
sound output from MPEG
decoder?
Does the
moving picture of the video
CD play on the screen
normally?
Does the audio sound
output normally?
END
Check power & clock.
Check CD/DVD DSP output
signal.
Check MPEG Decoder input
signal.
Check CD/DVD DSP output
signal.
Check MPEG Decoder input
signal.
Check CD/DVD DSP output
signal.
Check MPEG Decoder input
signal.
Check clock signal
Check clock signal
YES
YES
YES
YES YES
YES
YES
YES
YES
YES
NO
NO NO
OK OK
OK
OK
NO
NO
NO
NO
NO
3. MPEG Circuit
OPTION
If included VCD function.

2-7
Is LED On?
Check Power Circuit
Check the oscillation of X901
and Replace IC91 or X901
Check S902-S907, S909
Check Solder
Replace IC92
Check Solder
Check R904, 906, 909, 910,
R911, 916, 919, 924
Replace IC91OK
START
Power On Check Power Circuit.
4. Front Circuit (Digitron & Key)
NO
Check Q901, Q904, D902
Check L901
YES
YES
YES
YES
YES YES
YES YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO NO
NO
NO
NO NO
Is LED Off ?
Does bar appear
on FLD ?
Does "Main Error"
appear on FLD?
Check waveform of
IC91 Pin 14
Does all the buttons
work normally?
Does remote control
work normally?
Does waveform of
IC92 Pin 1 appear?
Is IC91 Pin 24 connected
to IC92 Pin 1 ?
Is 5V applied to
IC92 Pin 3 ?
Is 5.2V applied
to CN61 Pin 12 ?
Is HIGH State appear
on IC91 Pin 2 ?

2-8
Does signal pulse
input to IC201 Pins 58, 59 when
the powe is on?
Does signal goes
"High" to IC201 Pin194 when the
power is on?
Does
TTL pulse output to
IC201 Pins 140, 142?
Does
33.8688MHz clock input
to IC201 Pin 63?
Is IC201
Pins 83, 84, 88, 89 voltage
about 2.2V?
Replace IC201
(IC206 soldering or IC defect).
Check power circuit.
Check "2.µ-COM Part".
Replace X301 or IC304
(30MHz clock defect)
CHECK POINT(General)
5. RF/Servo Circuit
A.
END
NO
NO
NO NO
NO
YES
YES
YESYES
YES

2-9
Does tray open or close?
Does the pick-up
slide inner or outer
track?
Fig.1. SLED Driver waveform
Fig.2. Focus Driver waveform
Does
the voltage change
at PMD04 Pins 1, 2 more than
2V on the basis of
3.8V?
Pressing
the open/close key
repeatedly, check the voltage of IC2M1
Pins 13, 14 change
0V to 5V
Does
PMD03 Pin 7 change
high to low?
Does
the pick-up lens move up
and down?
Check Focus Driver output.
(IC201 Pin 83, IC2M1 Pins 37, 38)
Check SLED Driver output.
IC201 Pin 88 IC2M1 Pins 28, 29.
IC201 Pin 88 no output : IC201 is defective
IC2M1 Pin 18 no output : IC2M1 is defective
IC201 Pin 83 no output : IC201 is defective
IC2M1 Pins 1, 2 no output : IC2M1 is defective
DECK assembly is defective.
Slide the pick-up to
inner track.
.Power on Check loading Part.
Push Pick-up to inner track to
the end by hand.
DECK assembly is defective.
(Limit sw)
check µ-COM Part.
Replace IC2M1.
No disc
B.
END
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES

2-10
FOCUS ON?
Check
the focus error moving the
lens up and down.
(IC2A1 Pin 42)
Does the
TTL level change at IC201
Pin 78 and 132 moving
the lens?
Does the disc turn?
IC201 Pin169 is "High"?
Is OK the track jump. Does the signal
pulse appear at IC2A1 Pins
39, 29?
Does the screen appear?
OPEN/CLOSE
Replace µ-COM or IC201.
Replace IC201.
Check IC2A1 Pin 11,12,13,14
in DVD Mode
Fig.3. FOCUS ERROR waveform
IC201 no output : Pick-up is defective.
Check IC201 and IC2M1 when PMD03 Pin 6 is abnormal
Check IC2M1 Pin 21, PMD03
Pin 6 turn when the IC2M1
Pin 21 is less than 2.2V.
Check A
Video Part is defective.
Check "5.MPEG Circuit."
Check "7.OSD/Video Circuit."
Replace µ-COM part.
IC2A1 is defective.
DISC IN
C.
END
NO
NO
NO
NO NO
NO
NO
NO
YES YES
YES
YES
YES
YES YES
YES

2-11
Is the eye-pattern vivid?
Does the
sawtooth waveform emit
at IC2A1 Pin 41? Does the 1.6V emit?
Check RF Eye-Pattern.
RF : 1.5-1.6V(IC2A1 Pin 57)
Fig.5. RF
waveform
Check IC2A1 Pins 5, 6, 7, 8. No signal: Pick-up is defective
Replace IC201. Check IC201 Pin84.
No signal at IC201 : IC201 is defective
•Check IC201 Pin 162.
•Check the clock at the IC201 Pins 28, 30.
•Both are normal : IC201 is defective
Replace IC2A1.
CHECK A
D.
END
NO
NO NO NO
YES
YES YES YES