JVC TH-M303 User manual

SERVICE MANUAL
COPYRIGHT © 2004 VICTOR COMPANY OF JAPAN, LIMITED No.MB184
2004/3
DVD DIGITAL THEATER SYSTEM
MB18420043
TH-M303, TH-M301
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
Area suffix
J ----------------------------- U.S.A.
C -------------------------- Canada
Area suffix
J ----------------------------- U.S.A.
TH-M303
TH-M301

1-2 (No.MB184)
SPECIFICATION
Center unit (XV-THM606/XV-THM603/XV-THM505/XV-THM501/ XV-THM303/XV-THM301)
*1: Corresponding to Linear PCM, Dolby Digital, and DTS Digital Surround (with sampling frequency - 32 kHz, 44.1 kHz, 48 kHz)
Subwoofer (SP-PWM603/SP-PWM303/SP-PWM301)
*3: For SP-PWM301
Front speakers (SP-THM303F)
Surround speakers (SP-THM303S)
Center Speaker (SP-THM303C)
Designs & specifications are subject to change without notice.
Audio section Total Harmonic Distortion 0.02%
NOTE This value is measured at System cord CONNECTOR for reference.
Digital input *1 DIGITAL IN (DBS) (OPTICAL):
-21 dBm to -15 dBm (660 nm E30 nm)
Video section Video System NTSC
Horizontal Resolution 500 lines
Signal-to-Noise Ratio 64 dB
Video output level Composite:1.0 V(p-p)/75Ω
S-video-Y:1.0 V(p-p)/75Ω
S-video-C:0.286 V(p-p)/75Ω
Component-Y:1.0 V(p-p)/75Ω
Component-PB/PR:0.7 V(p-p)/75Ω
Video input sensitivity/Impedance
(VCR IN)
Composite:1.0 V(p-p)/75Ω
S-video-Y:1.0 V(p-p)/75Ω
S-video-C:0.286 V(p-p)/75Ω
Tuner section Tuning Range FM:87.5 MHz to 108.0 MHz
AM:530 kHz to 1 710 kHz
Power Requirements AC 120 V, 60 Hz
General Power Consumption 18 W (at operation) 2.0 W (in standby mode)
Dimensions (W ×H ×D) 400 mm ×85 mm ×380 mm (15-3/4 inches ×3-3/8 inches ×15 inches)
Mass 4.3 kg (9.5 lbs)
Amplifier section Front/Center/Surround 115 W (100 W *3) per channel, RMS at 4 Ω(Center/Surround)/ 125 W (115 W *3) per channel,
RMS at 4 Ω(Front) at 1 kHz, with 10 % total harmonic distortion.
Subwoofer 125 W (120 W *3), RMS at 4 Ωat 100 Hz, with 10 % total harmonic distortion.
Speaker section Speaker unit 16 cm (6-5/16 inches) Bass-reflex, Magnetically Shielded
Frequency Range 30 Hz to 200 Hz
General Power Requirements AC 120 V, 60 Hz
Power Consumption 125 W (at operation) 0 W (in standby mode)
Dimensions (W ×H ×D) 168.5 mm ×412 mm ×444 mm (6-11/16 inches ×16-1/4 inches ×17-1/2 inches)
Mass 12.0 kg (26.5 lbs)
Speakers 8.0 cm (3-3/16 inches) Bass-reflex, Magnetically Shielded
Power Handling Capacity 140 W
Impedance 4Ω
Frequency Range 90 Hz to 20 kHz
Dimensions (W ×H ×D) 106 mm ×119.5 mm ×102 mm (4-3/16 inches ×4-3/4 inches ×4-1/16 inches)
Mass 0.69 kg (1.6 lbs)
Speakers 8.0 cm (3-3/16 inches) Bass-reflex, Magnetically Shielded
Power Handling Capacity 140 W
Impedance 4Ω
Frequency Range 80 Hz to 20 kHz
Dimensions (W ×H ×D) 111.5 mm ×139 mm ×106.5 mm (4-7/16 inches ×5-1/2 inches ×4-1/4 inches)
Mass 0.63 kg (1.4 lbs)
Speakers 8.0 cm (3-3/16 inches) Bass-reflex, Magnetically Shielded
Power Handling Capacity 140 W
Impedance 4Ω
Frequency Range 90 Hz to 20 kHz
Dimensions (W ×H ×D) 106 mm ×119.5 mm ×102 mm (4-3/16 inches ×4-3/4 inches ×4-1/16 inches)
Mass 0.69 kg (1.6 lbs)

(No.MB184)1-3
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 from visual 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 be sure 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
exposed 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

1-4 (No.MB184)
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 to check the condition 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 flexible wire is disconnected from the connecto on the servo board. (If the flexible
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 flexible wire.
1M
Conductive material
(conductive sheet) or iron palate
(caption)
Anti-static wrist strap
Short circuit points

(No.MB184)1-5
1.8 Importance administering point on the safety
Caution: For continued protection against risk of fire,
replace only with same type 1.6A/125V for F901,
6.3A/125V for F101, 8A/125V for F153 and F154.
This symbol specifies type of fast operating fuse.
Precaution: Pour eviter risques de feux, remplacez
le fusible de surete de F901 comme le meme type
que 1.6A/125V, et 6.3A/125 pour F101, et 8A/125V
pour F153 et F154.
Ce sont des fusibles suretes qui functionnes rapide.
^
1.6A-125V
F901
6.3A-125V
F101
8A-125V
F154
8A-125V
F153
RY101
CN101
CN102
XV-THM303/XV-THM301 SP-PWM303/SP-PWM301

1-6 (No.MB184)
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.

(No.MB184)1-7
SECTION 3
DISASSEMBLY
3.1 Main body section
3.1.1 Removing the metal cover
(See Figs.1 to 4)
(1) From the both sides of the main body, remove the four
screws Aattaching the metal cover. (See Figs.1 and 2)
(2) From the back side of the main body, remove the three
screws Battaching the metal cover. (See Fig.3)
(3) Lift the rear section of the metal cover in the direction of the
arrow while extending the lower sections of the metal cov-
er, release the five claws ausing a longer screwdriver from
the inside as required. (See Fig.4)
Note:
Do not damage any parts and boards inside the main body
when releasing the claws ausing a longer screwdriver.
Fig.1
Fig.2
Fig.3
Fig.4
Metal cover
A
Metal cover
A
Metal cove
r
B
Metal cover
Claws aClaws a

1-8 (No.MB184)
3.1.2 Removing the front panel assembly
(See Figs.5 and 6)
• Prior to performing the following procedures, remove the metal
cover.
(1) From the top side of the main body, disconnect the parallel
wires from the connectors (CN456, CN457) on the main
board. (See Fig.5)
(2) Disconnect the card wires from the connectors (CN450,
CN460) on the main board. (See Fig.5)
(3) Remove the screw Cattaching the earth wire to the main
board. (See Fig.5)
Reference:
When attaching the screw C, attach the earth wire with
it. (See Fig.5)
(4) From the bottom side of the main body, remove the three
screws Dattaching the front panel assembly. (See Fig.6)
(5) From the both and bottom sides of the main body, remove
the front panel assembly in the direction of the arrow while
releasing the joints band c. (See Fig.6)
Fig.5
Fig.6
CN460
Main board
C
Card wire
Earth
wire
Front panel assembly
CN457
Parallel wires
CN450
CN456
Card wire
D
Joint cJoint bJoint b
Front panel assembly

(No.MB184)1-9
3.1.3 Removing the DVD changer mechanism assembly
(See Fig.7)
• Prior to performing the following procedures, remove metal
cover and front panel assembly.
(1) From the top side of the main body, disconnect the card
wires from the connectors (CN401 to CN403) on the main
board.
Reference:
When connecting the card wires, connect them to the
connectors (CN401 to CN403) on the main board after
passing the card wires through the hole d on the main
board.
(2) Remove the four screws Eattaching the DVD changer
mechanism assembly on the bottom chassis.
(3) Take out the DVD changer mechanism assembly in the up-
ward direction.
Reference:
When attaching the DVD changer mechanism assembly, align
the holes of the DVD changer mechanism assembly to the pro-
jections eon the bottom chassis.
Fig.7
3.1.4 Removing the rear panel
(See Fig.8)
• Prior to performing the following procedures, remove the metal
cover.
(1) From the back side of the main body, remove the screw F
and twelve screws Gattaching the rear panel.
Fig.8
Main board
CN402
Bottom chassis
DVD changer mechanism assembly
Card wires
E
E
E
Projections e
Hole d
CN401 CN403
FG
G
Rear panel

1-10 (No.MB184)
3.1.5 Removing the audio & digital input board
(See Figs.9 and 10)
• Prior to performing the following procedures, remove the metal
cover.
(1) From the top side of the main body, disconnect the card
wires from the connectors (CN411, CN412) on the main
board. (See Fig.9)
(2) Remove the screw Hattaching the audio & digital input
board to the bracket(DSP). (See Fig.9)
(3) From the back side of the main body, remove the screw J
and two screws Kattaching the audio & digital input board
to the rear panel. (See Fig.10)
(4) Take out the audio & digital input board from the main
body.
3.1.6 Removing the tuner
(See Figs.9 and 10)
• Prior to performing the following procedures, remove the metal
cover.
(1) From the top side of the main body, disconnect the card
wire from the connector CN1 on the tuner. (See Fig.9)
(2) From the back side of the main body, remove the two
screws Lattaching the tuner to the rear panel. (See Fig.10)
(3) Take out the tuner from the main body.
3.1.7 Removing the power supply board
(See Figs.9 and 10)
• Prior to performing the following procedures, remove the metal
cover.
(1) From the top side of the main body, disconnect the parallel
wires from the connectors (CN404 to CN407) on the main
board. (See Fig.9)
(2) Remove the three screws Mattaching the power supply
board. (See Fig.9)
(3) From the back side of the main body, remove the screw N
attaching the power supply board to the rear panel. (See
Fig.10)
(4) Take out the power supply board from the main body.
Reference:
Remove the rear panel as required. (See removing the rear
panel)
Fig.9
Fig.10
Power supply board
M
Bracket
(DSP)
Parallel wires
CN404
M
CN405
Tuner
CN1
Card wire
Audio & digital input board
CN407
CN406
H
Card wires
Main board
CN411
CN412
JN
Rear panel
KL

(No.MB184)1-11
3.1.8 Removing the main board
(See Fig.11)
• Prior to performing the following procedures, remove the metal
cover, rear panel, audio & digital input board and tuner.
(1) From the top side of the main body, disconnect the card
wires from the connectors (CN401 to CN403, CN450 and
CN460) on the main board.
Reference:
When reassembling, connect the card wires to the con-
nectors (CN401 to CN403) on the main board after pass-
ing the card wires through the hole f on the main board.
(2) Disconnect the parallel wires from the connectors (CN404
to CN407, CN456 and CN457) on the main board.
(3) From the top side of the main body, remove the two screws
Pand screw P' attaching the main board on the bottom
chassis.
Reference:
When attaching the screw P', attach the earth wire with
it. (See Fig.11)
(4) Take out the main board from the main body.
Fig.11
Main board
P
P'
P
Bottom chassis
Earth wire
CN404
CN407
CN406
CN405
CN402CN401 Hole
f
CN457
CN460 CN456
CN403
CN450

1-12 (No.MB184)
3.2 Front panel assembly section
• Prior to performing the following procedures, remove the metal
cover and front panel assembly.
3.2.1 Removing the phone jack board
(See Fig.1)
(1) From the inside of the front panel assembly, remove the
screw Aand screw A' attaching the phone jack board.
Reference:
• When attaching the phone jack board, align the projec-
tions aof the front panel assembly to the holes of the
phone jack board.
• When attaching the screw A', attach the earth wire
with it.
(2) Take out the phone jack board from the front panel assem-
bly.
3.2.2 Removing the connect board
(See Fig.1)
(1) From the inside of the front panel assembly, disconnect the
card wire from the connector CN561 on the connect board.
(2) Remove the two screws Battaching the connect board.
Reference:
When attaching the connect board, align the projections
bof the front panel assembly to the holes of the connect
board.
(3) Take out the connect board from the front panel assembly.
3.2.3 Removing the operation board
(See Fig.1)
(1) From the inside of the front panel assembly, remove the
three screws Cattaching the operation board.
Reference:
When attaching the operation board, align the projec-
tions cof the front panel assembly to the holes of the op-
eration board.
(2) Take out the operation board with the button(top).
Fig.1
3.2.4 Removing the front board
(See Figs.2 and 3)
• Prior to performing the following procedures, remove the oper-
ation board.
(1) From the front side of the front panel assembly, pull out the
volume knob in the direction of the arrow. (See Fig.2)
(2) From the inside of the front panel assembly, remove the
seven screws Dattaching the front board. (See Fig.3)
Reference:
When attaching the front board, align the projections dof
the front panel assembly to the holes of the front board.
(See Fig.3)
(3) Take out the front board and remove the solder from the
soldered point eto remove the parallel wire. (See Fig.3)
Fig.2
Fig.3
Earth wire
A' A
Projection aProjection a
Phone jack board
C
c
C
Operation board
Button (TOP)
B
Projection bProjection b
CN561
Connect board
Front panel assembly
Front panel assembly
Volume knob
D
Front panel assembly
D
D
D
Projections d
Projection dSolder point c
Parallel wire
Front board

(No.MB184)1-13
3.2.5 Removing the power key board
(See Fig.4)
(1) From the inside of the front panel assembly, remove the
two screws Eattaching the power key board.
Reference:
When attaching the power key board, align the projec-
tions fof the front panel assembly to the holes of the
power key board.
(2) Take out the power key board and remove the solder from
the soldered point gto remove the parallel wire.
Fig.4
3.2.6 Removing the illumination board
(See Figs.5 and 6)
(1) Open the DVD door of the front panel assembly and re-
move the three screws Fattaching the door holder to the
DVD door. (See Fig.5)
(2) Remove the DVD door from the door holder. (See Fig.5)
(3) From the inside of the DVD door, disconnect the card wire
from the connector CN551 on the illumination board. (See
Fig.6)
(4) Take out the illumination board from the DVD door.
Fig.5
Fig.6
Front panel assembly Parallel wire
E
E
Projection
f
Solder poitn g
Power key board
Projection f
Front panel assembly
Door holder
FDVD doo
r
Door holder
DVD door
Illumination board
CN551 Card wire

1-14 (No.MB184)
3.3 DVD changer mechanism assembly section
• Prior to performing the following procedures, remove the metal
cover, front panel assembly and the DVD changer mechanism
assembly.
3.3.1 Removing the tray assemblies
(See Figs.1 to 5)
(1) Remove the two screws Afrom the top cover and release
the two joints aon the both sides of the DVD changer
mechanism assembly. (See Figs.1 and 2)
(2) Remove the two rods from the top cover and remove the
top cover from the lifter assembly. (See Figs.1 and 2)
(3) Remove the open det lever on the left side of the DVD
changer mechanism assembly. (See Fig.3)
(4) From the right side of the DVD changer mechanism as-
sembly, draw out the tray assemblies toward the front while
pushing the part bof the side (R) assembly. (See Fig.4)
Attention:
The tray can be locked if all tray assemblies are at-
tached.
(5) From the top side of the DVD changer mechanism assem-
bly, move the stopper tabs cin the direction of the arrow
and release them. Pull out the tray assemblies from the
DVD changer mechanism assembly. (See Figs.4 and 5)
Caution:
Remove the tray assembly from top tray 5 in order.
Attention:
When reattaching the tray assembly, or when removing the
disc remaining inside, refer to another section "3.3.15 Taking
out the disc in the play mode".
Fig.1
Fig.2
Fig.3
Fig.4
Fig.5
Top cover
Lifter assembly
Rods
A
Joint a
Joint a
A
Joint a
Rods
Top cover
Lifter assembly
Joint a
Open det leve
r
b
Tray assembly
Stopper tab c
Side (R) assembly
Stopper tab c
Tray assembly

(No.MB184)1-15
3.3.2 Removing the DVD servo board
(See Figs.6 to 8)
• Prior to performing the following procedures, remove the tray
assemblies.
(1) From the topside of the DVD changer mechanism assem-
bly, solder the short-circuit points don the DVD pick up.
(See Fig.6)
Caution:
Solder the short-circuit points don the DVD pickup be-
fore disconnecting the flexible wire extending from the
DVD pickup. If you do not follow this instruction, the DVD
pickup may be damaged.
(2) From the bottom side of the DVD changer mechanism as-
sembly, disconnect the card wires from the connectors
CN201 and CN451 and the wires from the connectors
CN452 and CN453 on the DVD servo board. (See Fig.7)
(3) Remove the two screws Battaching the bracket to the DVD
changer mechanism assembly, and reverse the DVD servo
board. (See Fig.7)
(4) From the reverse side of the DVD servo board, disconnect
the card wire from the connector CN101 in the direction of
the arrow 1 on the DVD servo board. (See Fig.8)
(5) Take out the DVD servo board.
Caution:
Unsolder the solders from the short-circuit points dafter reas-
sembling.
Reference:
When connecting the card wire to the connector CN201, let the
wire through the slots e.
3.3.3 Removing the switch board
(See Fig.7)
(1) From the bottom side of the DVD changer mechanism as-
sembly, disconnect the wires from connectors CN452 and
CN453 on the DVD servo board.
(2) Remove the screw Cattaching the switch board to the DVD
changer mechanism assembly.
(3) Release the wires from the slots fof the switch board.
Caution:
When reassembling, let the wires through the slots fof the
switch board.
Fig.6
Fig.7
Fig.8
DVD pickup
DVD changer mechanism assembly
Short circuit points d
Card wire
CN451
CN201
DVD changer mechanism assembly
Switch board
DVD servo board
CN452
CN453
C
Slot e
Card
wire
Slot f
B
B
11 Card wire
CN101
DVD changer mechanism assembly
DVD servo board

1-16 (No.MB184)
3.3.4 Removing the motor board
(See Figs.9 and 10)
(1) From the top side of the DVD chnager mechanism assem-
bly, remove the two belts from the motor pulleys. (See
Fig.9)
Caution:
Take care not to attach grease on the belt.
(2) Remove the four screws Dattaching the motors to the
chassis assembly. (See Fig.9)
(3) From the bottom side of the DVD changer mechanism as-
sembly, remove the two screws E. (See Fig.10)
(4) Disconnect the connector CN2 on the motor board from the
tray switch board and remove the motor board. (See
Fig.10)
(5) Disconnect the card wire from the connector CN1 on the
motor board. (See Fig.10)
Caution:
• When connecting the card wire, let the card wire through the
slots gof the motor board. (See Fig.10)
• When reattaching the motor, turn the side where the label
should be put to the front side. (See Fig.10)
Reference:
You need not to remove the tray assemblies, and in such case,
move it.
3.3.5 Removing the motor
(See Fig. 10)
• Prior to performing the following procedures, remove the motor
board.
(1) From the reverse side of the motor board, unsolder the four
soldered sections hon the motor board.
(2) From the forward side of the motor board, remove the mo-
tors.
Fig.9
Fig.10
3.3.6 Removing the DVD traverse mechanism assembly
(See Fig.11)
• Prior to performing the following procedures, remove the tray
assemblies.
(1) From the top side of the DVD changer mechanism assem-
bly, disconnect the card wire from the connector CN451 on
the DVD servo board.
(2) Disconnect the wires from the connectors CN452 and
CN453 on the DVD servo board.
(3) Remove the three screws Fattaching the DVD traverse
mechanism assembly.
(4) Take out the DVD traverse mechanism assembly with DVD
servo board from the DVD changer mechanism assembly.
Fig.11
Motor Motor
Motor pulleys Chassis assembly
BeltBelt
D
D
E
Slots g
CN2
Card wire
Motors
Soldered sections h
CN1
E
Motor board
DVD changer mechanism assembly
Labels
Motors
Motor board
Card wire
CN451
F
F
DVD changer mechanism assembly
DVD traverse mechanism assembly
DVD servo board
CN452
CN453

(No.MB184)1-17
3.3.7 Removing the DVD pickup
(See Figs.12 to 14)
• Prior to performing the following procedures, remove the tray
assemblies and DVD traverse mechanism assembly.
(1) From the topside of the DVD traverse mechanism assem-
bly, solder the short-circuit points ion the DVD pick up.
(See Fig.12)
Caution:
Solder the short-circuit points ion the DVD pickup before
disconnecting the flexible wire extending from the DVD
pickup. If you do not follow this instruction, the DVD pick-
up may be damaged.
(2) Disconnect the flexible wire from the connector on the DVD
pickup. (See Fig.12)
(3) Turn the screw shaft gear in the direction of the arrow 1 to
move the DVD pickup in the direction of the arrow 2. (See
Fig.12)
(4) Remove the screw Gattaching the gear holder. (See
Fig.12)
(5) Remove the screw Hattaching the SS adj. spring. (See
Fig.12)
(6) Move the DVD pickup in the direction of the arrow and re-
move the screw shaft from the section jon the screw shaft
holder. (See Fig.13)
(7) Remove the section kof the DVD pickup from the guide
shaft. (See Fig.13)
(8) Remove the two screws Jattaching the rack arm to the
DVD pickup. (See Fig.14)
(9) Pull the screw shaft from the DVD pickup in the direction of
the arrow. (See Fig.14)
3.3.8 Attaching the DVD pickup
(See Figs.12 to 14)
(1) Attach the screw shaft to the DVD pickup and attach the
rack arm with the screws J. (See Fig.14)
Reference:
After attaching the screw shaft to the DVD pickup, attach
the screw shaft collar to the screw shaft. (See Fig.14)
(2) Attach the section kof the DVD pickup to the guide shaft
first and attach the screw shaft to the section jon the screw
shaft holder. (See Fig.14)
(3) Attach the SS adj. spring and gear holder with the screws
Gand H. (See Fig.12)
(4) Turn the screw shaft gear to move the DVD pickup toward
the left. (See Fig.12)
(5) Connect the flexible wire to the connector on the DVD pick-
up. (See Fig.12)
Caution:
Unsolder the solders from the short-circuit points iafter con-
necting the flexible wire.
Fig.12
Fig.13
Fig.14
Short circuit points i
SS adj. spring
Screw shaft
gear
Gear holder DVD pickup
Connector
HG
DVD traverse
mechanism assembly
Flexible wire
2
1
DVD pickup Guide shaft
Screw shaft Screw shaft holder
Section k
Section j
Screw shaft colla
r
Screw shaft
DVD pickup
Rack arm
J

1-18 (No.MB184)
3.3.9 Removing the spindle motor board
(See Figs.15 and 16)
• Prior to performing the following procedures, remove the tray
assemblies and DVD traverse mechanism assembly.
(1) From the topside of the DVD traverse mechanism assem-
bly, remove the four screws Kattaching the DVD traverse
mechanism assembly to the DVD traverse mechanism
base. (See Fig.15)
(2) Remove the wires from the soldered section mon the spin-
dle motor board. (See Fig.15)
(3) Remove the screw Lattaching the spindle motor board.
(See Fig.15)
(4) From the bottom side of the DVD traverse mechanism as-
sembly, remove the three screws Mattaching the spindle
motor board. (See Fig.16)
Reference:
When attaching the spindle motor board, let the card wire
through the hole non the motor base. (See Fig.15)
Fig.15
Fig.16
3.3.10 Removing the feed motor
(See Figs.17 and 18)
• Prior to performing the following procedures, remove the tray
assemblies, DVD traverse mechanism assembly, DVD pickup
and spindle motor board.
• Remove the wires of the feed motor as required.
(1) Remove the middle gear in the direction of the arrow. (See
Fig.17)
(2) Remove the screw Nand screw Pattaching the motor
base.
(3) Remove the screw Qattaching the feed motor to the motor
base. (See Fig.18)
(4) Take out the feed motor from the motor base.
Reference:
After attaching the feed motor, let the wires through the sec-
tions pand qon the motor base. (See Fig.17) Fig.17
Fig.18
Spindle motor board
Motor base
K
K
K
L
Hole n
Section m
DVD traverse mechanism assembly
DVD traverse mechanism base
Card wire
Wires
M
Feed motor
Middle
gear
P
N
Section q
Section p
Motor base
Traverse mechanism chassis
Feed motor
Motor base
Q

(No.MB184)1-19
3.3.11 Removing the side (L) assembly and tray switch board
(See Figs.19 to 23)
• Prior to performing the following procedures, remove the tray
assemblies.
(1) From the topside of the DVD changer mechanism assem-
bly, remove the two screws Rattaching the side (L) assem-
bly. (See Fig.19)
(2) From the left side of the DVD changer mechanism assem-
bly, removing the spacer fixing the tray switch board and
motor board. (See Fig.20)
(3) Disconnect the connector CN3 on the tray switch board
from the motor board and detach the side (L) assembly in
an upward direction. (See Fig.20)
(4) Remove the screw Sattaching the tray switch board to the
side (L) assembly. (See Fig.21)
(5) Release the joint tab rof the side (L) assembly in the direc-
tion of the arrow 1 and release the joint tab swhile remov-
ing the tray switch board in the direction of the arrow 2.
(See Fig.21)
Reference:
After attaching the tray switch board to the motor board, fix
them with spacers.
Fig.19
Fig.20
Fig.21
Fig.22
Fig.23
R
Side (L) assembly
R
CN3
Spacer
Side (L) assembly
R
R
Motor board
Side (L) assembly
Joint tab
r
Joint tab s
S
Tray switch board
Side (L) assembly 1
2
Tab s
Side (R) assembly
Side (R) assembly
Elevator spring
Gear cover
Elevator cam
Hook u
Gear
Chassis assembly

1-20 (No.MB184)
3.3.12 Removing the side (R) assembly
(See Fig.22 to 26)
• Prior to performing the following procedures, remove the tray
assemblies and DVD servo board.
• When removing the DVD servo board, it is not necessary to re-
move the DVD servo board from the bracket.
(1) From the inside of the side (R) assembly, release the two
tabs tof the gear cover and remove the gear cover out-
ward. (See Figs.22 and 23)
(2) From the right side of the DVD changer mechanism as-
sembly, remove the elevator spring attached to the hook u
of the chassis assembly. (See Figs.23 and 24)
(3) From the topside of the DVD changer mechanism assem-
bly, turn the gear 1 clockwise to move the elevator cam
rearward. (See Fig.24)
(4) Move the two slots vand joint wof the elevator cam and
remove the elevator cam outward. (See Fig.24)
(5) Remove the three screws Tand detach the side (R) as-
sembly upward. (See Figs.25 and 26)
Caution:
When reattaching the side (R) assembly, make sure to fit the
shaft section xinto the slot of the select lever. (See Fig.25)
Fig.24
Fig.25
Fig.26
Elevator cam
Elevator spring Hook u
Slot vSlot v
Joint w
T
Side (R) assembly
T
TSection xSelect leve
r
Side (R) assembly
T
T