JVC TH-G40C User manual

SERVICE MANUAL
COPYRIGHT © 2008 Victor Company of Japan, Limited No.MB672<Rev.002>
2008/9
DVD DIGITAL THEATER SYSTEM
MB672<Rev.002>20089SERVICE MANUAL TH-G40J, TH-G40C, TH-G40UJ,
TH-G30J, TH-G30C
COPYRIGHT © 2008 Victor Company of Japan, Limited
Lead free solder used in the board (material : Sn-Ag-Cu, melting point : 219 Centigrade)
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
2 SPECIFIC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
XV-THG40
XV-THG30
SP-THG50C
SP-THG50F SP-THG50F (for Rear) SP-THG50W
SP-THG50C
SP-THG50F SP-THG50F (for Rear) SP-THG50W
TH-G40
TH-G30

1-2 (No.MB672<Rev.002>)
SPECIFICATION
TH-G40
General
Power supply Refer to main label.
Power consumption Refer to main label.
Net Weight 4 kg
External dimensions (W x H x D) 430 x 72 x 307 mm
Operating conditions Temperature: 5°C to 35°C Operation status: Horizontal
Operating humidity 5% to 85%
Laser Semiconductor laser, wavelength 650 nm
CD/DVD
Video system NTSC
Frequency response (audio) 140 Hz to 20 kHz *
Signal-to-noise ratio (audio) More than 75 dB (1 kHz 20 kHz LPF/A-Filter) *
Dynamic range (audio) More than 75 dB *
Harmonic distortion (audio) 0.5 % (1 kHz at 1W position) (20 kHz LPF) *
Video
Video output 1.0 V (p-p) 75 Ωnegative sync. RCA jack x 1
COMPONENT VIDEO OUT (Y) 1.0 V (p-p) 75 ohms negative sync RCA jack x 1
(PB)/(PR) 0.7 V (p-p) 75 ohms RCA jack x 1
HDMI OUT 480p/720p/1080i/1080p
Tuner (FM)
Tuning Range 87.5 - 108.0 MHz
Intermediate Frequency 10.7 MHz
Signal-to Noise Ratio 60 dB (Mono) *
Frequency Response 140 - 10,000 Hz *
Amplifier
Stereo mode 155 W + 155 W (4Ωat 1 kHz, THD 10 %)
Surround mode
(* Depending on the sound mode settings
and the source there may be no sound output.)
Front: 155 W + 155 W (THD 10 %)
center*: 155 W
Surround*: 155 W + 155 W (4Ωat 1 kHz THD 10 %)
Subwoofer*: 225 W (3Ωat 70 Hz THD 10 %)
Inputs AUDIO IN, OPTICAL IN, AUX IN
Outputs MONITOR OUT HDMI OUT COMPONENT VIDEO OUT
Speakers
Front/Rear Speaker Type 1 Way 1 Speaker
Impedance 4 Ω
Frequency Response 120 - 20000 Hz
Sound Pressure Level 83 dB/W (1m)
Rated Input Power 155 W
Max. Input Power 310 W
Net Dimensions (W x H x D) 117 x 210 x 111 mm
Net Weight 0.9 kg

(No.MB672<Rev.002>)1-3
Items with * are measured at Front Speaker Terminals in STEREO mode
Designs and specifications are subject to change without notice.
TH-G40UJ
center speaker Type 1 Way 1 Speaker
Impedance 4 Ω
Frequency Response 120 -20000 Hz
Sound Pressure Level 83 dB/W (1m)
Rated Input Power 155 W
Max. Input Power 310 W
Net Dimensions (W x H x D) 300 x 115 x 111 mm
Net Weight 1.1 kg
Passive Subwoofer Type 1 Way 1 Speaker
Impedance 3 Ω
Frequency Response 40 - 1500 Hz
Sound Pressure Level 82 dB/W (1m)
Rated Input Power 225 W
Max. Input Power 450 W
Net Dimensions (W x H x D) 236 x 435 x 391 mm
Net Weight 5.7 kg
General
Power supply 110-240 V ~ 50/60 Hz
Power consumption 130 W
Net Weight 4 kg
External dimensions (W x H x D) 430 x 72 x 307 mm
Operating conditions Temperature: 5°C to 35°C,Operation status: Horizontal
Operating humidity 5% to 85%
Laser Semiconductor laser,wavelength 650 nm
CD/DVD
Video system NTSC
Frequency response (audio) 140 Hz to 20 kHz*
Signal-to-noise ratio (audio) More than 75 dB (1 kHz,20 kHz LPF/A-Filter)*
Dynamic range (audio) More than 75 dB*
Harmonic distortion (audio) 0.5 % (1 kHz,at 1W position) (20 kHz LPF)*
Video
Video output 1.0 V (p-p),75 Ω,negative sync.,RCA jack x 1
COMPONENT VIDEO OUT (Y) 1.0 V (p-p),75 ohms,negative sync,RCA jack x 1
(PB)/(PR) 0.7 V (p-p),75 ohms,RCA jack x 1
HDMI OUT 480p/720p/1080i/1080p
Tuner (FM)
Tuning Range 87.5 - 108.0 MHz
Intermediate Frequency 10.7 MHz
Signal-to Noise Ratio 60 dB (Mono)*
Frequency Response 140 - 10000 Hz*
Amplifier

1-4 (No.MB672<Rev.002>)
Items with * are measured at Front Speaker Terminals in STEREO mode
Designs and specifications are subject to change without notice.
Surround mode
(* Depending on the sound mode
settings and the source
there may be no sound output.)
Front: 155 W + 155 W (THD 10 %)
center*: 155 W
Surround*: 155 W + 155 W (4Ωat 1 kHz,THD 10 %)
Subwoofer*: 225 W (3Ωat 70 Hz,THD 10 %)
Inputs AUDIO IN,OPTICAL IN,AUX IN
Outputs MONITOR OUT,HDMI OUT,COMPONENT VIDEO OUT
Speakers
Front/Rear Speaker Type 1 Way 1 Speaker
Impedance 4 Ω
Frequency Response 120 - 20000 Hz
Sound Pressure Level 83 dB/W (1m)
Rated Input Power 155 W
Max. Input Power 310 W
Net Dimensions (W x H x D) 117 x 210 x 111 mm
Net Weight 0.9 kg
center speaker Type 1 Way 1 Speaker
Impedance 4 Ω
Frequency Response 120 -20000 Hz
Sound Pressure Level 83 dB/W (1m)
Rated Input Power 155 W
Max. Input Power 310 W
Net Dimensions (W x H x D) 300 x 115 x 111 mm
Net Weight 1.1 kg
Passive Subwoofer Type 1 Way 1 Speaker
Impedance 3 Ω
Frequency Response 40 - 1500 Hz
Sound Pressure Level 82 dB/W (1m)
Rated Input Power 225 W
Max. Input Power 450 W
Net Dimensions (W x H x D) 236 x 435 x 391 mm
Net Weight 5.7 kg

(No.MB672<Rev.002>)1-5
TH-G30
General
Power supply Refer to main label.
Power consumption Refer to main label.
Net Weight 4 kg
External dimensions (W x H x D) 430 x 72 x 307 mm
Operating conditions Temperature: 5°C to 35°C Operation status: Horizontal
Operating humidity 5% to 85%
Laser Semiconductor laser, wavelength 650 nm
CD/DVD
Video system NTSC
Frequency response (audio) 140 Hz to 20 kHz *
Signal-to-noise ratio (audio) More than 75 dB (1 kHz 20 kHz LPF/A-Filter) *
Dynamic range (audio) More than 75 dB *
Harmonic distortion (audio) 0.5 % (1 kHz at 1W position) (20 kHz LPF) *
Video
Video output 1.0 V (p-p) 75 Ωnegative sync. RCA jack x 1
COMPONENT VIDEO OUT (Y) 1.0 V (p-p) 75 ohms negative sync RCA jack x 1
(PB)/(PR) 0.7 V (p-p) 75 ohms RCA jack x 1
HDMI OUT 480p/720p/1080i/1080p
Tuner (FM)
Tuning Range 87.5 - 108.0 MHz
Intermediate Frequency 10.7 MHz
Signal-to Noise Ratio 60 dB (Mono) *
Frequency Response 140 - 10,000 Hz *
Amplifier
Stereo mode 155 W + 155 W (4Ωat 1 kHz, THD 10 %)
Surround mode
(* Depending on the sound mode settings
and the source there may be no sound output.)
Front: 155 W + 155 W (THD 10 %)
center*: 155 W
Surround*: 155 W + 155 W (4Ωat 1 kHz THD 10 %)
Subwoofer*: 225 W (3Ωat 70 Hz THD 10 %)
Inputs AUDIO IN, OPTICAL IN, AUX IN
Outputs MONITOR OUT HDMI OUT COMPONENT VIDEO OUT
Speakers
Front/Rear Speaker Type 1 Way 1 Speaker
Impedance 4 Ω
Frequency Response 120 - 20000 Hz
Sound Pressure Level 83 dB/W (1m)
Rated Input Power 155 W
Max. Input Power 310 W
Net Dimensions (W x H x D) 117 x 210 x 111 mm
Net Weight 0.9 kg

1-6 (No.MB672<Rev.002>)
Items with * are measured at Front Speaker Terminals in STEREO mode
Designs and specifications are subject to change without notice.
center speaker Type 1 Way 1 Speaker
Impedance 4 Ω
Frequency Response 120 -20000 Hz
Sound Pressure Level 83 dB/W (1m)
Rated Input Power 155 W
Max. Input Power 310 W
Net Dimensions (W x H x D) 300 x 115 x 111 mm
Net Weight 1.1 kg
Passive Subwoofer Type 1 Way 1 Speaker
Impedance 3 Ω
Frequency Response 40 - 1500 Hz
Sound Pressure Level 82 dB/W (1m)
Rated Input Power 225 W
Max. Input Power 450 W
Net Dimensions (W x H x D) 236 x 435 x 391 mm
Net Weight 5.7 kg

(No.MB672<Rev.002>)1-7
SECTION 1
PRECAUTION
1.1 Safety Precautions
(1) This design of this product contains special hardware and
many circuits and components specially for safety purpos-
es. For continued protection, no changes should be made
to the original design unless authorized in writing by the
manufacturer. Replacement parts must be identical to
those used in the original circuits. Services should be per-
formed by qualified personnel only.
(2) Alterations of the design or circuitry of the product should
not be made. Any design alterations of the product should
not be made. Any design alterations or additions will void
the manufacturers warranty and will further relieve the
manufacture of responsibility for personal injury or property
damage resulting therefrom.
(3) Many electrical and mechanical parts in the products have
special safety-related characteristics. These characteris-
tics are often not evident fromvisual inspection nor can the
protection afforded by them necessarily be obtained by us-
ing replacement components rated for higher voltage, watt-
age, etc. Replacement parts which have these special
safety characteristics are identified in the Parts List of Ser-
vice Manual. Electrical components having such features
are identified by shading on the schematics and by ( ) on
the Parts List in the Service Manual. The use of a substitute
replacement which does not have the same safety charac-
teristics as the recommended replacement parts shown in
the Parts List of Service Manual may create shock, fire, or
other hazards.
(4) The leads in the products are routed and dressed with ties,
clamps, tubings, barriers and the like to be separated from
live parts, high temperature parts, moving parts and/or
sharp edges for the prevention of electric shock and fire
hazard. When service is required, the original lead routing
and dress should be observed, and it should be confirmed
that they have been returned to normal, after reassem-
bling.
(5) Leakage shock hazard testing
After reassembling the product, always perform an isola-
tion check on the exposed metal parts of the product (an-
tenna terminals, knobs, metal cabinet, screw heads,
headphone jack, control shafts, etc.) to besure the product
is safe to operate without danger of electrical shock.Do not
use a line isolation transformer during this check.
• Plug the AC line cord directly into the AC outlet. Using a
"Leakage Current Tester", measure the leakage current
from each exposed metal parts of the cabinet, particular-
ly any exposed metal part having a return path to the
chassis, to a known good earth ground. Any leakage cur-
rent must not exceed 0.5mA AC (r.m.s.).
• Alternate check method
Plug the AC line cord directly into the AC outlet. Use an
AC voltmeter having, 1,000Ωper volt or more sensitivity
in the following manner. Connect a 1,500Ω10W resistor
paralleled by a 0.15µF AC-type capacitor between an ex-
posed metal part and a known good earth ground.
Measure the AC voltage across the resistor with the AC
voltmeter.
Move the resistor connection to each exposed metal
part, particularly any exposed metal part having a return
path to the chassis, and measure the AC voltage across
the resistor. Now, reverse the plug in the AC outlet and
repeat each measurement. Voltage measured any must
not exceed 0.75 V AC (r.m.s.). This corresponds to 0.5
mA AC (r.m.s.).
1.2 Warning
(1) This equipment has been designed and manufactured to
meet international safety standards.
(2) It is the legal responsibility of the repairer to ensure that
these safety standards are maintained.
(3) Repairs must be made in accordance with the relevant
safety standards.
(4) It is essential that safety critical components are replaced
by approved parts.
(5) If mains voltage selector is provided, check setting for local
voltage.
1.3 Caution
Burrs formed during molding may be left over on some parts
of the chassis.
Therefore, pay attention to such burrs in the case of pre-
forming repair of this system.
1.4 Critical parts for safety
In regard with component parts appearing on the silk-screen
printed side (parts side) of the PWB diagrams, the parts that are
printed over with black such as the resistor ( ), diode ( )
and ICP ( ) or identified by the " " mark nearby are critical
for safety. When replacing them, be sure to use the parts of the
same type and rating as specified by the manufacturer.
(This regulation dose not Except the J and C version)
Good earth ground
Place this
probe on
each exposed
metal part.
AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
1500 10W
0.15 F AC TYPE

1-8 (No.MB672<Rev.002>)
1.5 Preventing static electricity
Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser
diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.
1.5.1 Grounding to prevent damage by static electricity
Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as laser products.
Be careful to use proper grounding in the area where repairs are being performed.
(1) Ground the workbench
Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the
traverse unit (optical pickup) on it.
(2) Ground yourself
Use an anti-static wrist strap to release any static electricity built up in your body.
(3) Handling the optical pickup
• In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical
pickup are shorted. After replacement, return the shorted parts to their original condition.
(Refer to the text.)
• Do not use a tester tocheckthecondition of the laser diode in the optical pickup. The tester's internal power source can easily
destroy the laser diode.
1.6 Handling the traverse unit (optical pickup)
(1) Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.
(2) Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to the
replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a
time when attaching it to the connector.
(3) Handle the flexible cable carefully as it may break when subjected to strong force.
(4) I t is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.
1.7 Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for the pickup unit.
• Apply solder to the short land sections before the card wire is disconnected from the connecto on the servo board. (If the card wire
is disconnected without applying solder, the pickup may be destroyed by static electricity.)
• In the assembly, be sure to remove solder from the short land sections after connecting the card wire.
1M Conductive material
(conductive sheet) or iron palate
(caption)
Anti-static wrist strap
Solder short land section

(No.MB672<Rev.002>)1-9
1.8 Important for laser products
1.CLASS 1 LASER PRODUCT
2.CAUTION :
(For U.S.A.) Visible and/or invisible class II laser radiation
when open. Do not stare into beam.
(Others) Visible and/or invisible class 1M laser radiation
when open. Do not view directly with optical instruments.
3.CAUTION : Visible and/or invisible laser radiation when
open and inter lock failed or defeated. Avoid direct
exposure to beam.
4.CAUTION : This laser product uses visible and/or invisible
laser radiation and is equipped with safety switches which
prevent emission of radiation when the drawer is open and
the safety interlocks have failed or are defeated. It is
dangerous to defeat the safety switches.
5.CAUTION : If safety switches malfunction, the laser is able
to function.
6.CAUTION : Use of controls, adjustments or performance of
procedures other than those specified here in may result in
hazardous radiation exposure.
!Please use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.

1-10 (No.MB672<Rev.002>)
1.9 Importance admistering point on the safety
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.
Graphic symbol mark
(This symbol means slow blow type fuse.)
FOR CONTINUED PROTECTION AGAINST RISK
OF FIRE, REPLACE ONLY WITH SAME TYPE
AND RATING OF FUSES ;
should be read as follows ;
F901 : T12AH 250V F901 : T12AH 250V
Full Fuse Replacement Marking
FUSE CAUTION
Le symbole graphique (Ce symbole signifie
fusible de type a fusion lent.)
POUR UNE PROTECTION CONTINUE CONTRE
DES RISQUES D'INCENDIE, REMPLACER
SEULEMENT PAR UN FUSIBLE DU MEME TYPE ;
Marquage Pour Le Remplacement
Complet De Fusible
PRECAUTIONS SUR LES FUSIBLES
doit etre interprete comme suit ;
^
slow blow type / type a fusion lent

(No.MB672<Rev.002>)1-11
SECTION 3
DISASSEMBLY
3.1 Main body
3.1.1 Removing the Metal cover (See Fig. 1, 2)
(1) Remove the three screws Aattaching the Metal cover.
(See Fig.1)
(2) Remove the four screws Battaching the both side of the
Metal cover. (See Fig.2) Fig.1
Fig.2
3.1.2 Removing the Front Panel (See Fig. 3 to 6)
(1) Disconnect the card wire from Front panel connected to
connector PN103 of the Amp board. (See Fig.3)
(2) From the top side of the Front panel, disengage three
hooks aengaged Front panel. (See Fig.4)
(3) From the both side of the Front panel, disengage two
hooks bengaged Front panel. (See Fig.5)
(4) From the bottom side of the Front panel, disengage three
hooks cengaged Front panel. (See Fig.6)
Fig.3
Fig.4
Fig.5
Fig.6
A
B
PN103
hook a
hook b
hook c

1-12 (No.MB672<Rev.002>)
3.1.3 Removing the HDMI board (See Fig. 7, 8)
(1) Remove the one screw Cattaching the HDMI board. (See
Fig.7)
(2) Disconnect the card wire from Main board connected to
connector CN810 of the HDMI board. (See Fig.8)
(3) Remove the three screws Dattaching the HDMI board.
(See Fig.8)
Fig.7
Fig.8
3.1.4 Removing the DVD mechanism (See Fig.9)
(1) Disconnect the card wires from DVD mechanism connect-
ed to connector P400 and P401 of the Main board.
(2) Remove the four screws Eattaching the DVD mechanism.
Fig.9
C
D
CN810
EE
P400P401

(No.MB672<Rev.002>)1-13
3.1.5 Removing the Rear panel (See Fig.10, 11)
(1) Disconnect the Power cord from connector PN901 of the
SMPS board. (See Fig.10)
(2) Disconnect the connector wire from FAN connected to con-
nector PN603 of the Amp board. (See Fig.10)
(3) Remove the one screw Fand seven screws Gattaching
the Rear panel. (See Fig.11)
Fig.10
Fig.11
3.1.6 Removing the Front jack board (See Fig.12)
(1) Disconnect the card wire from Front jack board connected
to connector PN204 of the Main board.
(2) Remove the two screws Hattaching the Front jack board.
Fig.12
PN901
PN603
G
F
H
PN204

1-14 (No.MB672<Rev.002>)
3.1.7 Removing the Main board (See Fig.13, 14)
(1) Remove the two screws Jattaching the bracket. (See
Fig.13)
(2) Disconnect the connector wire from Main board connected
to connector CN901 of the SMPS board. (See Fig.14)
(3) Disconnect the card wires from Amp board connected to
connector PN202 and PN203 of the Main board. (See
Fig.14)
(4) Remove the two screws Kattaching the Main board. (See
Fig.14)
Fig.13
Fig.14
3.1.8 Removing the SMPS board (See Fig.15)
(1) Disconnect the connector wire from Amp board connected
to connector CN602 of the SMPS board.
(2) Remove the five screws Lattaching the SMPS board.
Fig.15
J
K
CN901
PN202
PN203
CN602
L

(No.MB672<Rev.002>)1-15
3.1.9 Removing the Amp board (See Fig.16)
(1) Remove the four screws Mattaching the Amp board.
Fig.16
3.1.10 Removing the Front key board (See Fig.17)
(1) Remove the one screw Nattaching the Front key board.
Fig.17
3.1.11 Removing the FL board (See Fig.18)
(1) Remove the five screws Pattaching the FL board.
Fig.18
M
N
P

1-16 (No.MB672<Rev.002>)
3.2 DVD mechanism
3.2.1 Main base (See Fig.1)
(1) Place the disc clamp assembly as Fig.1.
(2) Lift up thedisc clamp assembly in direction of the arrow (A).
(3) Separate the disc clamp assembly from the Clamp holder.
(4) Turn the Clamper plate to counterclockwise direction and
then lift up the clamper plate.
Fig.1
3.2.2 Disc tray (See Fig.2)
(1) Insert and push a screwdriver in the emergency eject hole
(A) at the right side, or put the screwdriver on the lever (B)
of the emergency gear and pull the lever (B) in direction of
arrow so that the Disc tray is ejected about 15 ~ 20 mm.
(2) Pull the Disc tray until it is separated from the Main base
completely.
Fig.2
Main base
Clamper plate
Magnet clamp
Upper clamp
Clamp holder
Main base
(Fig.A)
Disc clamp assembly
(A)
Disc tray
Main base
Lever
Main base
BOTTOM SIDE VIEW
(B)

(No.MB672<Rev.002>)1-17
3.2.3 Slide base assembly (See Fig.3)
(1) Release the four screws (S2).
(2) Disconnect the FFC connector (C1).
(3) Release the screw (S3).
Fig.3
Pickup base
Distinguish upper and
lower sides
(Assemble with care)
Rubber damper
Rubber damper
Rubber damper
Reck gear
General pickup assembly
Spindle motor assembly
(S2)
(S2)
(S2)
(S2)
(S3)
(C1)

1-18 (No.MB672<Rev.002>)
3.2.4 Up/Down frame assembly (See Fig.4)
NOTE:
Put the Main base face down (Bottom side)
(1) Release the screw (S4).
(2) Unlock theLockingtab (L3) in directionof arrowand thenlift up theUp/down frame assembly to separate it fromthe Mainbase.
NOTE:
When reassembling move the Up/Down guide in direction of arrow (C) until it is positioned as Fig (C).
When reassembling insert (A) position of the Up/down frame assembly in the (B) position of the Up/down frame assembly as Fig (B).
3.2.5 Pulley gear (See Fig.4)
(1) Unlock the locking tab (L4) in direction of arrow (B) and then separate the pulley gear from the main base.
3.2.6 Up/down guide (See Fig.4)
(1) Move the Up/down guide in direction of arrow (A) as Fig (A).
(2) Push the locking tab (L5) down and then lift up the Up/down guide to separate it from the main base.
NOTE:
When reassemblingplace the Up/down guide asFig (C) and move it direction arrow (B) until it is locked by the locking tab (L5). And
confirm the Up/down guide as Fig (A).
3.2.7 Loading board assembly (See Fig.4)
(1) Release one screw (S5).
(2) Unlock the loading motor (C2) from the hook (H1) on the main base.
(3) Unlock two locking tabs (L6) and separate the loading board assembly from the main base.
Fig.4
Loading gear
Pully gear
Loading belt
Loading board assembly
Main base
Up/Down guide
Up/Down guide
Up/Down guide
Up/Down frame assembly
Up/Down guide
Main base
(L6)
(L4) (L6)
(H1)
(C2)
(S5)
(L3)
(S4)
(S4)
(A)
(A)
(B)
(B)(C)
FIG. (A) FIG. (B)
FIG. (C)
Screw insertion
torque control
(A)
(L5) (B)

(No.MB672<Rev.002>)1-19
SECTION 4
ADJUSTMENT
This service manual does not describe ADJUSTMENT.

1-20 (No.MB672<Rev.002>)
SECTION 5
TROUBLESHOOTING
5.1 Power Supply Circuit
YES
NO
NO
NO
NO
NO
Check power plug and power
supply circuit.
Check power supply circuit.
Check laser circuit.
Check focus circuit.
Check disc.
Check tracking servo circuit.
Check audio circuit.
Is the Digitron on correctly?
YES
Is power on?
YES
Does initial read work?
YES
Does it play?
YES
Does it output
audio?
YES
YES
Turn power on.
Insert power cord.
OK