JVC TH-A55 User manual

SERVICE MANUAL
COPYRIGHT © 2003 VICTOR COMPANY OF JAPAN, LIMITED No.MB108
2003/12
DVD DIGITAL CINEMA SYSTEM
MB108200312 TH-A55
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
2 SPECIFIC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
Area suffix
A ------------------------- Australia

1-2 (No.MB108)
SPECIFICATION
Designs & specifications are subject to change without notice.
Center unit
Audio Audio input sensitivity/Impedance (at 1 kHz), Total Harmonic Distortion 0.01 %
NOTE:
This value is measured at System cord CONNECTOR for reference.
Analog input AUDIO IN VCR 360 mV/47 kΩ
Digital input* DIGITAL IN (DBS) (OPTICAL) -21 dBm to -15 dBm (660 nm ±30 nm)
* Corresponding to Linear PCM, Dolby Digital, and DTS Digital Surround (with sampling frequency - 32 kHz, 44.1 kHz, 48 kHz)
Video Color System NTSC/PAL selectable
Horizontal Resolution 500 lines
Signal-to-Noise Ratio 64 dB
Video output level Composite 1.0 V(p-p)/75 Ω
S-video-Y 1.0 V(p-p)/75 Ω
S-video-C 0.286 V(p-p)/75 Ω
Component-Y 1.0 V(p-p)/75 Ω
Component-PB/PR 0.7 V(p-p)/75 Ω
Video input sensitivity/
Impedance (VCR IN) Composite 1.0 V(p-p)/75 Ω
S-video-Y 1.0 V(p-p)/75 Ω
S-video-C 0.286 V(p-p)/75 Ω
Tuner Tuning Range FM 87.50 MHz to 108.00 MHz
AM 531 kHz to 1 602 kHz (at 9 kHz intervals)
530 kHz to 1 600 kHz (at 10 kHz intervals)
General Power Requirements AC 240 V ·, 50 Hz
Power Consumption 20 W (at operation) 2.5 W (in standby mode)
Dimensions (W ×H ×D) 398 mm ×70 mm ×265 mm
Mass 2.7 kg Subwoofer
Amplifier Front/Center/Surround 80 W per channel, RMS at 6 Ωat 1 kHz, with 10 % total harmonic distortion.
Subwoofer 120 W, RMS at 4 Ωat 100 Hz, with 10 % total harmonic distortion.
Speaker Speaker unit 20 cm Bass-reflex, Magnetically Shielded
Frequency Range 25 Hz to 200 Hz
General Power Requirements AC 240 V, 50 Hz
Power Consumption 150 W (at operation) 0 W (in standby mode)
Dimensions (W ×H ×D) 235 mm ×355 mm ×492 mm
Mass 13.0 kg Front Speakers
Speakers 8 cm Bass-reflex, Magnetically Shielded
Power Handling Capacity 80 W
Impedance 6 Ω
Frequency Range 80 Hz to 20 kHz
Dimensions (W ×H ×D) 103 mm ×194 mm ×128 mm
Mass 0.77 kg Center Speaker
Speakers 8 cm Bass-reflex, Magnetically Shielded
Power Handling Capacity 80 W
Impedance 6 Ω
Frequency Range 80 Hz to 20 kHz
Dimensions (W ×H ×D) 165 mm ×130 mm ×128 mm
Mass 0.77 kg Surround Speakers
Speakers 8 cm Bass-reflex, Magnetically Shielded
Power Handling Capacity 80 W
Impedance 6 Ω
Frequency Range 80 Hz to 20 kHz
Dimensions (W ×H ×D) 103 mm ×194 mm ×128 mm
Mass 0.64 kg

(No.MB108)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 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

1-4 (No.MB108)
1.5 Preventing static electricity
1.5.1 Grounding to prevent damage by 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.
1.5.2 About the earth processing for the destruction prevention by static electricity
Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD players.
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.
1.5.3 Handling the optical pickup
(1) In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical pick-
up are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.)
(2) 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.
1.5.4 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) Remove solder of the short lands on the flexible wire after replacing the optical pickup. For specific details, refer to the replace-
ment 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 wire carefully as it may break when subjected to strong force.
(4) It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.
1.5.5 Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for the DVD pickup.
• Apply solder to the short circuit points before the flexible wire is disconnected from the connector on the DVD pickup.
(If the flexible wire is disconnected without applying solder, the DVD pickup may be destroyed by static electricity.)
• In the assembly, be sure to remove solder from the short circuit points after connecting the flexible wire.
Conductive material
(conductive sheet) or iron plate
(caption)
Anti-static wrist strap
DVD mechanism assembly
CN101
DVD servo board
Short land sections
Flexible wire

(No.MB108)1-5
1.6 Important for laser products
(1) CLASS 1 LASER PRODUCT
(2) DANGER : Invisible laser radiation when open and inter
lock failed or defeated. Avoid direct exposure to beam.
(3) CAUTION : There are no serviceable parts inside the
Laser Unit. Do not disassemble the Laser Unit. Replace the
complete Laser Unit if it malfunctions.
(4) CAUTION : The compact disc player uses 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 herein may result in
hazardous radiation exposure.
CAUTION
Please use enough caution not to see the beam directly
or touch it in case of an adjustment or operation check.
VARNING
Osynlig laserstrålning är denna del är öppnad osh spårren är
urkopplad. Betrakta ej strålen.
VARO
Avattaessa ja suojalukitus ohitettaessa olet alttiina näkymät-
tömälle lasersäteilylle. Älä katso säteeseen.
ADVARSEL
Usynlig laserstråling ved åbning, når sikkerhedsafbrydere er
ude af funktion. Undgå udsasttelse for stråling.
ADVARSEL
Usynlig laserstråling ved åpning, når sikkerhetsbryteren er
avslott. Unngå utsettelse for stråling.
REPRODUCTION AND POSITION OF LABELS
CLASS 1
LASER PRODUCT
CAUTION LABEL

1-6 (No.MB108)
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.

(No.MB108)1-7
SECTION 3
DISASSEMBLY
3.1 Main body section
3.1.1 Removing the top panel
(See Fig.1)
(1) From the top side of the main body, remove the four screws
Aattaching the top panel.
(2) Remove the top panel from main body.
Fig.1
3.1.2 Removing the rear cover
(See Figs.2 and 3)
• Prior to performing the following procedures, remove the top
panel.
(1) From the rear side of the main body, remove the three
screws Battaching the rear cover. (See Fig.2)
(2) From the top side of the main body, remove the two screws
Cand two screws Dattaching the rear cover. (See Fig.3)
(3) Remove the rear cover upward.
Fig.2
Fig.3
3.1.3 Removing the rear panel
(See Fig.4)
• Prior to performing the following procedures, remove the top
panel and rear cover.
(1) From the rear side of the main body, remove the eight
screws Eand screw Fattaching the rear panel.
(2) Remove the rear panel from main body.
Fig.4
AA
Top panel
B
Rear cover
CC
D
Rear cover
E
FE
Rear panel

1-8 (No.MB108)
3.1.4 Removing the front panel assembly
(See Figs.5 and 6)
• Prior to performing the following procedures, remove the top
panel.
(1) From the top side of the head phone board, remove the
three screws Gattaching the front panel assembly. (See
Fig.5)
(2) Disconnect the card wires from the connectors CN408 and
CN412 on the main board. (See Fig.5)
(3) Extend the side of the front panel assembly in the direction
of the arrows a. (See Fig.5)
(4) Remove the front panel assembly in the direction of the ar-
rows c, while releasing the claw b. (See Fig.6)
Fig.5
Fig.6
3.1.5 Removing the DVD mechanism assembly
(See Figs.7 and 8)
• Prior to performing the following procedures, remove the top
panel and rear cover.
(1) From the top side of the main body, remove the two screws
Hand screw Jon the DVD mechanism assembly. (See
Fig.7)
(2) Disconnect the connectors CN502 and CN503 on the DVD
servo board from the connectors CN405 and CN406 on the
main board while lifting the DVD mechanism assembly up-
ward. (See Fig.8)
(3) Take out the DVD mechanism assembly from the main
board.
Fig.7
Fig.8
G
G
Front panel
assembly
aa
CN412
CN408 Head phone
board
Main board
Front panel
assembly
claw b
c
c
H
J
DVD mechanism
assembly
CN503
CN502
CN406 CN405
DVD mechanism
assembly
DVD servo
board
Main board

(No.MB108)1-9
3.1.6 Removing the DSP board
(See Figs.9 and 10)
• Prior to performing the following procedures, remove the top
panel and rear cover.
(1) From the top side of the DSP board, disconnect the card
wires from the connectors CN401 on the DSP board. (See
Fig.10)
(2) Remove the screw Kattaching the DSP board from the
section dof the barrier. (See Fig.10)
(3) From the back side of the main body, remove the screw L
and two screws Mattaching the DSP board. (See Fig.9)
Reference:
• When attaching the DSP board, hang the DSP board on the
section dof the barrier. (See Fig.10)
3.1.7 Removing the tuner
(See Figs.9 and 11)
• Prior to performing the following procedures, remove the top
panel, rear cover and DSP board.
(1) From the top side of the tuner, disconnect the card wire
from the connector CN1 on the tuner. (See Fig.11)
(2) From the back side of the main body, remove the two
screws Nattaching the tuner. (See Fig.9)
(3) Take out the tuner from the main body.
Fig.9
Fig.10
Fig.11
N
LM
Rear panel
K
Section d
CN401
DSP board
CN1
Tuner

1-10 (No.MB108)
3.1.8 Removing the main board
(See Fig.12)
• Prior to performing the following procedures, remove the top
panel, rear cover, rear panel, DVD mechanism, DSP board
and tuner.
(1) From the top side of the main board, disconnect the card
wires from the connectors CN408 and CN412 on the main
board.
(2) From the top side of the power board, disconnect the card
wires from the connectors CN901 and CN902 on the power
board.
(3) Remove the three screws Pattaching the main board.
(4) Take out the main board from the main body.
Reference:
• After connecting the wire to the connectors CN901 and
CN902 on the power board, bundle the wire by the wire
clamp.
Fig.12
3.1.9 Removing the power board
(See Fig.13)
• Prior to performing the following procedures, remove the top
panel, rear cover and rear panel.
(1) From the top side of the main body, disconnect the card
wires from the connectors CN901 and CN902 on the power
board.
(2) Remove the four screws Qattaching the power board.
(3) Take out the power board from the bottom chassis.
Reference:
• Remove the front panel assembly and DVD mechanism as-
sembly as required.
• After connecting the wire to the connectors CN901 and
CN902 on the power board, bundle the wire by the wire
clamp.
Fig.13
P
P
CN408
CN412 CN901
Wire clamp Power board
Main board
CN902
Q
Q
CN901
CN902
Wire clamp
Power board

(No.MB108)1-11
3.2 Front panel assembly section
• Prior to performing the following procedures, remove the top
panel and front panel assembly.
3.2.1 Removing the FL board
(See Figs.1 and 2)
(1) From the inside of the FL board, disconnect the wire from
the connector CN502 on the volume board. (See Fig.2)
(2) Remove the FL board in the direction of the arrow e, while
lifting the claws fupward. (See Fig.1)
(3) Take out the FL board from front panel assembly.
Reference:
• Before attaching the FL board, be careful not to damage the
projection part g.
• Before attaching the FL board, insert FL board in the section
h.
3.2.2 Removing the head phone board
(See Fig.1)
• Remove the screw Rattaching the head phone board, take out
the head phone board. Fig.1
Fig.2
3.2.3 Removing the switch board
(See Fig.3)
• Prior to performing the following procedures, remove the FL
board.
• Remove the two screws Sattaching the switch board, take out
the switch board.
3.2.4 Removing the volume board
(See Fig.3)
• Prior to performing the following procedures, remove the FL
board.
• Remove the two screws Tattaching the volume board, take out
the volume board. Fig.3
Claw f
R
Claw f
ee
Projection part gFL board
Head phone board
Claw fClaw f
Section hFL board
CN502
ST
Switch board Volume board

1-12 (No.MB108)
3.3 DVD mechanism section
• Prior to performing the following procedures, remove the top plate
and rear cover, and remove the DVD mechanism assembly.
3.3.1 Removing the tray
(See Figs.1 and 2)
(1) From the left side of the DVD mechanism assembly, push
the slide cam in the direction of the arrow 1 and then pull
out the tray in the direction of the arrow 2. (See Fig.1)
(2) Push the tray stoppers ain the direction of the arrow 3, pull
out the tray in the direction of the arrow 4. (See Fig.2)
3.3.2 Attaching the tray
(See Fig.2)
When attaching the tray, insert the tray to the rail of the DVD
mechanism assembly and then push the tray in the DVD mech-
anism assembly. Fig.1
Fig.2
3.3.3 Removing the DVD servo board
(See Fig.3)
(1) From the bottom side of the DVD mechanism assembly,
disconnect the card wires from the connectors CN201 and
CN202 on the DVD servo board.
Caution:
disconnecting the flexible wire from connector CN101 on
the DVD servo board.
If the flexible wire is disconnected without attaching sol-
der, the DVD pickup unit may be destroyed by static
electricity.
(2) Release the locks of the connector CN101 (in the direction
of the arrow 1) on the DVD servo board, disconnect the
flexible wire.
(3) Release the locks of the connector CN101 on the DVD ser-
vo board in the direction of the arrow 1, disconnect the flex-
ible wire.
Caution:
In the assembly, be sure to remove solders from the
short land sections bafter connecting the flexible wire to
the connector CN101 on the DVD servo board.
(4) While pushing the claw cof the DVD mechanism assembly
in the direction of the arrow 2, remove the DVD servo board
in an upward direction.
Fig.3
2
Tray
Slide cam
1
DVD mechanism assembly
Tray
Tray stoppers a
3
4
DVD mechanism assembly
Claw c
Claw c
CN201
CN202
CN101
DVD servo board
11
222
Short land sections b
Card wire
Card wire
Flexible wire

(No.MB108)1-13
3.3.4 Removing the clamper base
(See Fig.4)
(1) From the top side of the DVD mechanism assembly, re-
move the four screws Aattaching the clamper base.
(2) Remove the clamper base from the bosses dof the loading
base in an upward direction, remove the clamper base
from the sections ewhile sliding it in the direction of the ar-
row.
Fig.4
3.3.5 Removing the tray drive board
(See Fig.5)
• Prior to performing the following procedures, remove the
clamper base.
(1) From the bottom side of the DVD mechanism assembly, re-
move the solders from the soldered sections fon the tray
drive board.
(2) Remove the screw Battaching the tray drive board to the
DVD mechanism assembly.
Fig.5
Clamper base
AA
Boss d
Boss dA A
Section e
Section e
Loading base
Motor Tray drive board
DVD mechanism assembly
B
Soldered
sections f
Connector
Card wire

1-14 (No.MB108)
3.3.6 Removing the motor
(See Fig.6)
• Prior to performing the following procedures, remove the
clamper base and tray drive board.
(1) From the top side of the DVD mechanism assembly, re-
move the belt of the pulley gear.
Note:
Take care not to attach grease on the belt.
(2) Remove the screw Cattaching the motor to the DVD mech-
anism assembly.
Fig.6
3.3.7 Removing the DVD traverse mechanism assembly
(See Fig.7)
• Prior to performing the following procedures, remove the DVD
servo board and clamper base.
(1) From the top side of the DVD mechanism assembly, re-
move the four screws Dattaching the DVD traverse mech-
anism assembly to the loading base.
(2) Take out the DVD traverse mechanism assembly from the
loading base.
Fig.7
DVD mechanism assembly
Belt
C
Motor
Pulley gear
DVD traverse mechanism assembly
D D
DD
Loading base

(No.MB108)1-15
3.3.8 Removing the DVD pickup unit
(See Figs.8 to 10)
• Prior to performing the following procedures, remove the DVD
servo board, clamper base and DVD traverse mechanism as-
sembly.
(1) From the top side of the DVD traverse mechanism assem-
bly, remove the screw Eattaching the plate and torsion
spring. (See Fig.8)
(2) Remove the shaft from the section gand then remove the
shaft from the section h. (See Fig.9)
(3) Disengage the section iof the DVD pickup unit and then re-
move the DVD pickup unit with the shaft. (See Fig.9)
(4) Pull the shaft out of the DVD pickup unit. (See Fig.10)
(5) Remove the two screws Fattaching the SW. actuator. (See
Fig.10)
3.3.9 Attaching the DVD pickup unit
(See Figs.8, 10 to 12)
Reference:
Refer to the explanation of "Removing the DVD pickup unit" on
the preceding page.
(1) Attach the SW. actuator and shaft to the DVD pickup unit.
(See Fig.10)
(2) Engage the section iof the DVD pickup unit to the shaft of
the DVD traverse mechanism assembly first, and set the
both ends of the shaft of the DVD pickup unit in the sections
gand hof the DVD traverse mechanism assembly. (See
Fig.11)
(3) Slide the DVD pickup unit all the way in the direction of the
arrow. (See Fig.12)
(4) Mesh the lead screw to the section jof DVD pickup unit and
then set the end of the lead screw to the section k. (See
Fig.12)
(5) Attach the torsion spring. (See Fig.8)
(6) Attach the plate. (See Fig.8)
Fig.8
Fig.9
Fig.10
Fig.11
Fig.12
E
Plate
Torsion spring DVD pickup unit
DVD traverse mechanism assembly
DVD pickup unit
Shaf
t
Section h
Section g
Section i
Shaft
DVD pickup uni
t
F
SW. actuator
Section i
DVD traverse mechanism assembly
Shaft
Section g
Section h
DVD pickup unit
Section k
Section j
Lead scre
w
DVD pickup unit

1-16 (No.MB108)
3.3.10 Removing the spindle motor board
(See Figs.13 and 14)
• Prior to performing the following procedures, remove the DVD
servo board, clamper base and DVD traverse mechanism as-
sembly.
(1) From the top side of the DVD traverse mechanism assem-
bly, remove the feed motor wire that is soldered to the spin-
dle motor board. (See Fig.13)
(2) From the bottom side of the DVD traverse mechanism as-
sembly, remove the three screws Gattaching the spindle
motor board. (See Fig.14)
Fig.13
Fig.14
Remove the solders.
DVD traverse mechanism assembly
Spindle motor board
Feed moto
r
wire
G
G
DVD traverse mechanism assembly

(No.MB108)1-17
3.3.11 Removing the feed motor
(See Figs.15 to 17)
• Prior to performing the following procedures, remove the DVD
servo board, clamper base and DVD traverse mechanism as-
sembly.
(1) From the top side of the DVD traverse mechanism assem-
bly, remove the feed motor wire that is soldered to the spin-
dle motor board. (See Fig.15)
(2) Remove the screw Hattaching the feed holder assembly
and then take out the feed holder assembly. (See Fig.15)
(3) Remove the screw Jattaching the thrust spring. (See
Fig.16)
(4) Remove the feed gear and lead screw in the direction of the
arrow. (See Fig.16)
(5) Remove the two screws Kattaching the feed motor. (See
Fig.17)
Fig.15
Fig.16
Fig.17
H
Feed motor
H
Remove the solders.
DVD traverse mechanism assembly
Feed motor
wire
Spindle motor board
Feed holde
r
assembly
Feed holder assembly
J
Feed motor
Feed gear
Lead screw
Thrust spring
Feed holder assembly
K

1-18 (No.MB108)
3.4 Speaker section
3.4.1 Removing the amplifier assembly
(See Figs.1 and 2)
(1) From the rear side of the speaker main body, remove four
screws Aattaching the heat sink cover. (See Fig.1)
(2) Remove the nine screws Battaching amplifier assembly.
(See Fig.2)
(3) Move the amplifier assembly backward and disconnect the
wire from connector CN402 in the lower part ofthe amplifier
assembly. (See Fig.2)
Fig.1
Fig.2
A
A
Amplifier
assembly
Heat sink
cover
B
B
B
A
mplifier
assembly
CN402

(No.MB108)1-19
3.4.2 Removing the rear panel
(See Fig.3)
• Prior to performing the following procedures, remove the am-
plifier assembly.
(1) Remove the four screws C, twelve screws Dand screw E
attaching the rear panel.
(2) Take out the rear panel from the amplifier assembly.
Fig.3
3.4.3 Removing the SP terminal board
(See Figs.4 and 5)
• Prior to performing the following procedures, remove the am-
plifier assembly and rear panel.
(1) From the top side of the amplifier assembly, disconnect the
card wires from the connectors CN101 and CN102 on the
mother board. (See Figs.4 and 5)
(2) Disconnect the connectors CN401, CN403 and CN404 on
the SP terminal board from the connectors CN501, CN503
and CN504 on the mother board while lifting the SP termi-
nal board upward. (See Fig.5)
(3) Take out the SP terminal board from the amplifier assem-
bly.
Reference:
When attaching the SP terminal board, insert the SP terminal
board in the section aof the barrier.
Fig.4
Fig.5
CD
D
D
C
C
ED
Rear panel
C
D
Section a
Amplifier
assembly
Tie band
SP terminal
board
Mother
board
CN102
CN101
Amplifier
assembly
Tie band SP terminal
board
Mother
board
CN501
CN401
CN403
CN404
CN503
CN504
CN101
CN102

1-20 (No.MB108)
3.4.4 Removing the mother board assembly
(See Fig.6)
• Prior to performing the following procedures, remove the am-
plifier assembly, rear panel and SP terminal board.
(1) From the top side of the amplifier assembly, disconnect the
card wires from the connectors CN151 on the mother
board.
(2) From the top side of the amplifier assembly, remove the
five screws Fattaching the mother board.
(3) Take out the mother board assembly from the amplifier as-
sembly.
Fig.6
3.4.5 Removing the mother board
(See Fig.7)
• Prior to performing the following procedures, remove the am-
plifier assembly, rear panel, SP terminal board and mother
board assembly.
(1) From the bottom side of the mother board, remove the two
screws Gand two screws Hattaching the mother board.
(2) Disconnect the connectors CN521, CN522, CN531 and
CN532 on the mother board while lifting the mother board
upward, and take out the mother board.
Fig.7
Amplifier
assembly
Mother
board
CN151
FF
Mother board
CN522 CN531
CN532
CN521
H
H
G
G