JVC MX-GA9V User manual

SERVICE MANUAL
COPYRIGHT © 2003 VICTOR COMPANY OF JAPAN, LIMITED No.MB011
2003/10
COMPACT COMPONENT SYSTEM
MB01120039MX-GA9V
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
2 SPECIFIC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-36
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-40
COMPACT
DIGITAL VIDEO
COMPACT
DIGITAL AUDIO
Area Suffix
UX ---------- Saudi Arabia
UN ------------------ Asean
U ------------- Other Areas

1-2 (No.MB011)
SPECIFICATION
Amplifier section
Output Power SUB WOOFERS 88 W per channel, min. RMS, both channels driven into 6 Ωat 63
Hz with no more than 0.9% total harmonic distortion.
MAIN SPEAKERS 28 W per channel, min. RMS, both channels driven into 6 Ωat 1
kHz with no more than 0.9% total harmonic distortion.
Audio input sensitivity/Impedance
(Measured at 1 kHz, with tape
recording signal 300 mV)
AUX 390 mV/50 kΩ
MIC 1/2 3.0 mV/5 kΩ
Digital output CD OPTICAL DIGITAL OUTPUT
Signal wave length 660 nm
Output level -15 dBm to -12 dBm
Speakers/Impedance SUB WOOFERS 6 Ω- 16 Ω
MAIN SPEAKERS 6 Ω- 16 Ω
SURROUND SPEAKERS 16 Ω- 32 Ω
Tuner
FM tuning range 87.50 MHz - 108.00 MHz
AM tuning range For Saudi Arabia At 9 kHz intervals : 531 kHz - 1 602 kHz
At 10 kHz intervals : 530 kHz - 1 600 kHz
For other countries At 9 kHz intervals : 531 kHz - 1 710 kHz
At 10 kHz intervals : 530 kHz - 1 710 kHz
CD player
CD capacity 3 CDs
Dynamic range 85 dB
Signal-to-noise ratio 90 dB
Wow and flutter Immeasurable
Cassette deck
Frequency response Normal (type I) 50 Hz - 14 000 Hz
Wow and flutter 0.15% (WRMS)
General
Power requirement AC 110 V / AC 127 V / AC 220 V / AC 230 V - AC 240 V~(adjustable with the voltage selector),
50 Hz / 60 Hz
Power consumption 170 W (at operation) 25 W (on standby)
Dimensions (approx.) 265 mm ×335 mm ×401 mm (W/H/D) (10 7/16 in. ×13 1/4 in. ×15 13/16 in.)
Mass (approx.) 10.0 kg (22.1 lbs)

(No.MB011)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.MB011)
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 CD 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.
(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 CD pickup unit.
• Apply solder to the short land sections before the flexible wire is disconnected from the connector on the CD servo board. (If the
flexible wire is disconnected without applying solder, the CD 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
Soldering
CD changer
mechanism
assembly
CD traverse
unit
Flexible cable

(No.MB011)1-5
1.8 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 de
feated. 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.
REPRODUCTION AND POSITION OF LABEL and PRINT
WARNING LABEL and PRINT
!Please use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.
CLASS 1
LASER PRODUCT

1-6 (No.MB011)
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.

(No.MB011)1-7
SECTION 3
DISASSEMBLY
3.1 Main body
3.1.1 Removing the metal cover
(See Fig.1 ~ 3)
(1) Remove the six screws Aon the back of the body.
(2) Remove the two screws Bon both sides of the body.
(3) Remove the metal cover from the body by lifting the rear
part of the cover.
CAUTION:
Do not break the front panel tab fitted to the metal cover.
Fig.1
Fig.2
Fig.3
A
A
A
Metal cover
Metal cover
B
Metal cover
B

1-8 (No.MB011)
3.1.2 Removing the CD changer mechanism assembly
(See Fig.4 ~ 6)
• Prior to performing the following procedure, remove the metal
cover.
(1) Disconnect the wire from connector CN705 on the amplifier
board.
(2) Remove the plastic rivet attaching the main board to the
front assembly on the right side of the body.
(3) Disconnect the card wire from connector CN661 on the
main board.
(4) Remove the two screws Con the upper side of the body
and the two screws Don the back of the rear panel.
(5) Pull both the rear panel and the front panel assembly to the
outside, then remove the CD changer mechanism assem-
bly by lifting the rear part of the assembly.
REFERENCE:
At this point, one card wire on the underside of the CD
mechanism assembly is still connected.
(6) Disconnect the card wire from connector CN504 on the in-
ner side of the main board on the right side of the body. Re-
move the CD mechanism assembly.
CAUTION:
To prevent damage to the CD fitting, be sure to pull both the
rear panel and the front panel assembly enough to remove the
CD changer mechanism assembly.
Fig.4
Fig.5
Fig.6
3.1.3 Removing the fan
(See Fig.7)
• Prior to performing the following procedure, remove the metal
cover and the CD changer mechanism assembly.
(1) Turn over the CD changer mechanism assembly and re-
move the two screws Eattaching the fan.
Fig.7
CD changer mechanism assembly
Front panel assembly
Amplifier board
CN705
Rear panel
Front panel assembly
C
C
CD changer
mechanism assembly
Rear panel
Main board
CN661
CN504
CD changer mechanism assembly
D
Main board
CN661
Front panel assembly
Rear panel
CN504
Plastic rivet
Fan
E
E
CD changer mechanism assembly

(No.MB011)1-9
3.1.4 Removing the front panel assembly
(See Fig.8 ~ 11)
• Prior to performing the following procedure, remove the metal
cover and CD changer mechanism assembly.
(1) Disconnect the card wires from connector CN870, CN871
and CN315 on the main board respectively.
(2) Remove the wire clamp and disconnect the wire from con-
nector CN703 on the amplifier board.
(3) Disconnect the wire from connector CN220 on the trans-
former board.
(4) Remove the four screws Fon the bottom of the body.
(5) Release the two joints aon the lower right and left sides of
the body using a screwdriver, and remove the front panel
assembly toward the front.
Fig.8
Fig.9
Fig.10
Fig.11
3.1.5 Removing the tuner board
(See Fig.12)
• Prior to performing the following procedure, remove the metal
cover.
(1) Disconnect the card wire from connector CN1 on the tuner
board on the right side of the body.
(2) Remove the plastic rivet fixing the tuner board.
(3) Remove the two screws Gon the back of the body.
Fig.12
Wire clamp
A
mplifier board
CN703
Main board
CN870
CN871
CN315
Transformer board
CN220
Front panel
assembly
F
(Bottom)
(Bottom)
(Bottom)
Joint a
Front panel assembly
Front panel assembly
Joint a
CN1
Plastic rivet
Tuner board
Rear panel
G

1-10 (No.MB011)
3.1.6 Removing the rear cover / rear panel
(See Fig.13 ~ 16)
• Prior to performing the following procedure, remove the metal
cover and the CD changer mechanism assembly.
(1) Remove the screw Hattaching the rear cover on the back
of the body.
(2) Push each tab of the four joints bin the direction of the ar-
row and release.
(3) Remove the sixteen screws Gattaching the rear panel.
(4) Disengage the joints con each lower side of the rear panel
using a screwdriver and remove the rear panel backward.
Fig.13
Fig.14
Fig.15
Fig.16
Rear panel
H
Joint b
Joint b
Rear cover
G
Rear panel
G
G
GG
G
Joint c
Rear panel
Joint c Rear panel

(No.MB011)1-11
3.1.7 Removing the main board
(See Fig.17 ~ 19)
• Prior to performing the following procedure, remove the metal
cover, the CD changer mechanism assembly, the rear panel
and the antenna board.
(1) Disconnect the card wires from connector CN870, CN871
and CN315 on the main board.
(2) Disconnect the wires from connector CN704 and CN706
on the amplifier board.
(3) Disconnect the wire from connector CN710 on the speaker
board.
(4) Remove the screw Iattaching the main board on the right
side ofthe body.
(5) Disconnect connector CN211 and CN212 on the main
board from the regulator board.
3.1.8 Removing the speaker board
(See Fig.19)
• Prior to performing the following procedure, remove the metal
cover, the CD changer mechanism assembly and the rear pan-
el.
REFERENCE:
It is not necessary to remove the main board.
(1) Disconnect connector CN217 on the speaker board from
the regulator board.
(2) Disconnect the wire from connector CN710 on the speaker
board.
Fig.17
Fig.18
Fig.19
Front panel assembly
A
mplifier board
CN704
CN706
Speaker board
CN710
Main board
CN870
CN871
CN315
Main board
Front panel assembly
ICN211
CN212
Regulator board
Regulator board
CN217
Speaker board
CN710

1-12 (No.MB011)
3.1.9 Removing the power board
(See Fig.20)
• Prior to performing the following procedure, remove the metal
cover, the CD changer mechanism assembly and the rear pan-
el.
(1) Remove a wire clamp on the power board.
(2) Disconnect the wire from connector CN218, CN219 and
CN250 on the power board.
(3) Disconnect connector CN213 on the power board from the
regulator board.
Fig.20
3.1.10 Removing the amplifier board / voltage board / heat sink
(See Fig.21, 22)
• Prior to performing the following procedure, remove the metal
cover, the CD changer mechanism assembly and the rear pan-
el.
(1) Disconnect the wires from connector CN703, CN704 and
CN706 on the amplifier board respectively.
(2) Remove the two wire clamps attaching the wire to the am-
plifier board and the voltage board.
(3) Disconnect connector CN215 on the amplifier board and
CN216 on the voltage board from the regulator board (The
heat sink will be detached at once).
(4) Remove the four screws Jattaching the amplifier board to
the heat sink.
(5) Remove the two screws K, the board bracket and the volt-
age board.
REFERENCE:
It is not necessary to remove the power board.
Fig.21
Fig.22
CN218
Power board
CN219
Wire clamp
CN213
CN250
Amplifier board
CN704
CN706
CN216
Regulator board
CN215
Wire clamp
Wire clamp
CN703
Voltage board
Amplifier board
Heat sink
Voltage board
J
J
K

(No.MB011)1-13
3.1.11 Removing the power transformer assembly
(See Fig.23, 24)
• Prior to performing the following procedure, remove the metal
cover, the CD changer mechanism assembly and the rear pan-
el.
(1) Disconnect the wires from connector CN218 and CN219
on the power board.
(2) Disconnect the wire from connector CN204 on the regula-
tor board.
(3) Release the wire from the stopper on the regulator board.
(4) Remove the four screws Lattaching the transformer as-
sembly.
Fig.23
Fig.24
CN219
Regulator board
CN204
Power transformer assembly
Power board
CN218
Power transformer
assembly Regulator board
CN204
LL
Stopper

1-14 (No.MB011)
3.1.12 Removing the regulator board
(See Fig.25)
• Prior to performing the following procedure, remove metal cov-
er, CD changer mechanism assembly, rear panel, antenna
board, main board, amplifier board, voltage board, power
board and speaker board.
(1) Disconnect the wire from connector CN204 on the regula-
tor board.
(2) Release the wire from the stopper on the regulator board.
(3) Remove the two screws Mattaching the reglator board.
Fig.25
3.1.13 Removing the power cord
(See Fig.26)
• Prior to performing the following procedure, remove the metal
cover, the CD changer mechanism assembly and the rear pan-
el.
(1) Disconnect the wire from connector CN250 on the power
board.
(2) Remove the wire clamp from the power board.
(3) Move the power cord stopper upward and pull out it from
the base chassis.
Fig.26
M
M
Power transformer assembly Regulator board
CN204
Stopper
Power board
CN250
Power cord stopper
Wire clamp
Base chassis

(No.MB011)1-15
3.2 Front panel assembly
• Prior to performing the following procedure, remove the metal
cover, the CD changer mechanism assembly and the front
panel assembly.
3.2.1 Removing the cassette mechanism assembly
(See Fig.27)
(1) Disconnect the card wire from connector CN306 on the
head amplifier & mechanism control board.
(2) Remove the seven screws Nattaching the cassette mech-
anism assembly.
Fig.27
Head amplifier
& mechanismcontrol board
CN306 N
N
N
N
Cassette mechanism
assembly

1-16 (No.MB011)
3.2.2 Removing the display system control board
(See Fig.28 ~ 30)
(1) Remove the four screws Oattaching the stay bracket.
(2) Disconnect the card wires from connector CN316 and
CN880 on the display system control board.
(3) Remove the seven screws Pattaching the display system
control board.
(4) If necessary, disconnect the wire from connector CN911 on
the front side of the display system control board and un-
solder FW915.
3.2.3 Removing the CD eject board
(See Fig.30, 31)
(1) Remove the three screws Qattaching the CD eject board.
(2) If necessary, unsolder FW915 on the CD eject board.
Fig.28
Fig.29
Fig.30
Fig.31
O
Display system control board Stay bracket
P
P
P
P
CN316
CN880
FW915
(Solding)
P
Display system control board
FW915
FW915
CD eject board
CN911
Display system control board
CD eject board
FW915
(Solding)
Q
Q

(No.MB011)1-17
3.2.4 Removing the preset / tuning switch board
(See Fig.32, 33)
• Prior to performing the following procedure, remove the dis-
play system control board.
(1) Pull out the preset knob on the front panel.
(2) Remove the four screws Rattaching the preset / tuning
switch board.
(3) If necessary, unsolder FW901 on the preset / tuning switch
board.
3.2.5 Removing the operation switch board
(See Fig.33, 34)
• Prior to performing the following procedure, remove the dis-
play system control board and the preset / tuning switch board.
(1) Pull out the volume knob on the front panel and remove the
nut. Pull out the surround mode knob, the mic level knob
and the surround woofer level knob toward the front.
(2) Remove the twelve screws Sattaching the operation
switch board.
(3) Release each tab of the seven joints dretaining the opera-
tion switch board.
Fig.32
Fig.33
Fig.34
Preset / tuning switch board
R
R
Volume knob
Nut
Surround woofer
level knob
Surround mode knob
Preset knob
Mic level knob
S
SSS
S
S
S
Joint d
Joint d
Joint d
Joint d
Joint d
Operation
switch board

1-18 (No.MB011)
3.3 CD Changer Mechanism
• Remove the CD changer mechanism assembly.
3.3.1 Removing the CD Servo control board
(See Fig.1)
(1) From bottom side the CD changer mechanism assem-
bly,remove the four screws Aretaining the CD servo con-
trol board.
(2) Absorb the four soldered positions aof the right and left
motors with a soldering absorber.
(3) Pull out the earth wire on the CD changer mechanism as-
sembly.
(4) Disconnect the connector CN854 on the CD servo control
board.
(5) Disconnect the card wire CN601 and the connector CN801
on the CD servo control board.
Fig.1
aa
A
A
AA
CD servo control board
CN854
CN651
CN151
CN801
CN601

(No.MB011)1-19
3.3.2 Removing the CD tray assembly
(See Fig.2~9)
(1) Remove the CD servo control board.
(2) Remove the screw Bretaining the lod stopper.
(3) From the T.bracket section band clamper base section c ,
remove both of the edges fixing the rod.
(4) Remove the three screws Cretaining the T.bracket.
(5) Remove the screw Dretaining the clamper assembly.
(6) From the left side face of the chassis assembly, remove the
one screw Eretaining both of the return spring and lock le-
ver.
(7) By removing the pawl at the section dfixing the return
spring, dismount the return spring.
(8) Remove the three lock levers.
(9) Check whether the lifter unit stopper has been caught into
the hole at the section eof CD tray assembly as shown in
Fig.5.
(10) Make sure that the driver unit elevator is positioned as
shown in Fig.6 from to the second or fifth hole on the left
side face of the CD changer mechanism assembly.
CAUTION:
In case the driver unit elevator is not at above position,
set the elevator to the position as shown in Fig.7 by man-
ually turning the pulley gear as shown in Fig.8.
(11) Manually turn the motor pulley in the clockwise direction
until the lifter unit stopper is lowered from the section eof
CD tray assembly.
(12) Pull out all of the three stages of CD tray assembly in the
arrow direction funtil these stages stop.
(13) At the position where the CD tray assembly has stopped,
pull out the CD tray assembly while pressing the two pawls
gand g' on the back side of CD tray assembly. In this
case, it is easy to pull out the assembly when it is pulled out
first from the stage CD tray assembly.
Fig.2
Fig.3
Fig.4
Fig.5
b
c
Rod
T.Braket
Clamper base
T.Braket
Lod stopper
(C/J version only)
Clamper assembly
CC
B
D
C
E
d
Lock lever
Return spring
CD tray
assembly
e
Stopper

1-20 (No.MB011)
Fig.6
Fig.7
Fig.8
Fig.9
3.3.3 Removing the CD loading mechanism assembly
(See Fig.10)
(1) While turning the cams R1 and R2 assembly in the arrow
direction h,align the shaft iof the CD loading mechanism
assembly to the position shown in Fig.10.
(2) Remove the four screws Fretaining the CD loading mech-
anism assembly.
Fig.10
CD tray assembly
f
Refer to Fig.7 Pawl
Chassis assembly
g
Drive unit of elevato
r
CD 3
CD 2
CD 1
Pulley gear
Motor pulley
Pawl g, g'
CD tray assembly
Cams R1, R2 assembly
i
CD loading mechanism assembly
h
F
F
FF
A
rrow