Sony CDX-GT490US, CDX-GT494U, CDX-GT490U, CDX-GT49UM Service Manual

SERVICE MANUAL

Sony Corporation

Audio&Video Business Group
Published by Sony Techno Create Corporation

CDX-GT49UM/GT490U/

GT490US/GT494U

FM/AM COMPACT DISC PLA YER

9-889-625-02

2009K04-1

©

2009.11

E Model

CDX-GT490U/GT490US

Indian Model

CDX-GT49UM/GT494U

Ver. 1.1 2009.11

SPECIFICATIONS

Tuner section
FM

Tuning range:

Except Saudi Arabia model:

87.5 – 108.0 MHz (at 50 kHz step)

87.5 – 107.9 MHz (at 200 kHz step)
Saudi Arabia model:

87.5 – 108.0 MHz
FM tuning interval:
Except Saudi Arabia model:
50 kHz/200 kHz switchable

Antenna (aerial) terminal:

External antenna (aerial) connector

Intermediate frequency: 150 kHz
Usable sensitivity: 10 dBf
Selectivity: 75 dB at 400 kHz
Signal-to-noise ratio: 70 dB (mono)
Separation: 40 dB at 1 kHz
Frequency response: 20 – 15,000 Hz

AM

Tuning range:

Except Saudi Arabia model:
531 – 1,602 kHz (at 9 kHz step)
530 – 1,710 kHz (at 10 kHz step)
Saudi Arabia model:
531 – 1,602 kHz
AM tuning interval:
Except Saudi Arabia model:
9 kHz/10 kHz switchable

Antenna (aerial) terminal:

External antenna (aerial) connector

Intermediate frequency: 25 kHz
Sensitivity: 26 PV

CD player section

Signal-to-noise ratio: 120 dB
Frequency response: 10 – 20,000 Hz
Wow and fl utter: Below measurable limit

USB Player section

Interface: USB (Full-speed)
Maximum current: 500 mA

Power amplifi er section

Outputs: Speaker outputs (sure seal connectors)
Speaker impedance: 4 – 8 ohms
Maximum power output: 52 W u 4 (at 4 ohms)

General

Outputs:

Audio outputs terminal
(front, sub/rear switchable)
Power antenna (aerial) relay control terminal
Power amplifi er control terminal

Inputs:

Remote controller input terminal
Antenna (aerial) input terminal
AUX input jack (stereo mini jack)
USB signal input terminal

Model Name Using Similar Mechanism CDX-GT33U
CD Drive Mechanism Type MG-101Y-188//Q
Optical Pick-up Name DAX-25A

• The tuner and CD sections have no adjustments.

Tone controls:

Low: ±10 dB at 60 Hz (XPLOD)
Mid: ±10 dB at 1 kHz (XPLOD)
High: ±10 dB at 10 kHz (XPLOD)
Power requirements: 12 V DC car battery
(negative ground (earth))
Dimensions: Approx. 178 × 50 × 179 mm
(7

1

/8 × 2 × 7 1/8 in.) (w/h/d)

Mounting dimensions:

Approx. 182 × 53 × 162 mm
(7

1

/4 × 2 1/8 × 6 1/2 in.) (w/h/d)

Mass: Approx. 1.2 kg (2 lb. 11 oz.)
Supplied accessories:

Card remote commander: RM-X151
Parts for installation and connections (1 set)

Design and specifi cations are subject to change
without notice.

Photo: CDX-GT490US

CDX-GT49UM/GT490U/GT490US/GT494U

2

NOTES ON CHIP COMPONENT REPLACEMENT

• Never reuse a disconnected chip component.

• Notice that the minus side of a tantalum capacitor may be
damaged by heat.

TEST DISCS

Please use the following test discs for the check on the CD
section.

YDES-18 (Part No. 3-702-101-01)
PATD-012 (Part No. 4-225-203-01)

SAFETY-RELATED COMPONET WARNING!

COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE
WITH MARK 0 ON THE SCHEMATIC DIAGRAMS AND IN
THE PARTS LIST ARE CRITICAL TO SAFE OPERATION.
REPLACE THESE COMPONENTS WITH SONY PARTS
WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS
MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY.

NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electrostat­ic break-down because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also
use the procedure in the printed matter which is included in the
repair parts.
The fl exible board is easily damaged and should be handled with
care.

NOTES ON LASER DIODE EMISSION CHECK

The laser beam on this model is concentrated so as to be focused
on the disc refl ective surface by the objective lens in the optical
pickup block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.

CAUTION

Use of controls or adjustments or performance of procedures
other than those specifi ed herein may result in hazardous radia­tion exposure.

If the optical pick-up block is defective, please replace the whole
optical pick-up block.
Never turn the semi-fi xed resistor located at the side of optical
pick-up block.

optical pick-up

semi-fixed resistor

CDX-GT49UM/GT490U/GT490US/GT494U

3

UNLEADED SOLDER

Boards requiring use of unleaded solder are printed with the lead­free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with

the lead free mark due to their particular size)

: LEAD FREE MARK

Unleaded solder has the following characteristics.

• Unleaded solder melts at a temperature about 40 °C higher
than ordinary solder.

Ordinary soldering irons can be used but the iron tip has to be

applied to the solder joint for a slightly longer time.

Soldering irons using a temperature regulator should be set to

about 350 °C.
Caution: The printed pattern (copper foil) may peel away if

the heated tip is applied for too long, so be careful!

• Strong viscosity

Unleaded solder is more viscous (sticky, less prone to fl ow)

than ordinary solder so use caution not to let solder bridges
occur such as on IC pins, etc.

• Usable with ordinary solder

It is best to use only unleaded solder but unleaded solder may

also be added to ordinary solder.

This label is located on the bottom of the chassis.

1. SERVICE NOTE ...................................................... 4

2. GENERAL

Connections .................................................................... 5

3. DISASSEMBLY

3-1. Sub Panel Assy ............................................................... 9

3-2. CD Mechanism Block ..................................................... 9

3-3. Main Board ..................................................................... 10

3-4. Servo Board .................................................................... 10

3-5. Chassis (T) Sub Assy ...................................................... 11

3-6. Roller Arm Assy .............................................................. 11

3-7. Chassis (OP) Assy ........................................................... 12

3-8. Chucking Arm Sub Assy ................................................. 12

3-9. Sled Motor Assy .............................................................. 13

3-10. Optical Pick-up Section .................................................. 14

3-11. Optical Pick-up ............................................................... 14

4. DIAGRAMS

4-1. Block Diagram –Main Section– ..................................... 15

4-2. Block Diagram –Display Section– ................................. 16

4-3. Printed Wiring Board –Main Section– ............................ 18

4-4. Schematic Diagram –Main Section (1/3)– ...................... 19

4-5. Schematic Diagram –Main Section (2/3)– ...................... 20

4-6. Schematic Diagram –Main Section (3/3)– ...................... 21

4-7. Printed Wiring Boards –Key Section– ............................ 22

4-8. Schematic Diagram –Key Section– ................................ 23

5. EXPLODED VIEWS

5-1. Main Section ................................................................... 29

5-2. Front Panel Section ......................................................... 30

5-3. CD Mechanism Section (MG-101Y-188//Q) .................. 31

6. ELECTRICAL PARTS LIST .................................. 32

TABLE OF CONTENTS

CDX-GT49UM/GT490U/GT490US/GT494U

4

SECTION 1

SERVICE NOTE

EXTENSION CABLE AND SERVICE POSITION

When repairing or servicing this set, connect the jig (extension
cable) as shown below.

• Connect the MAIN board (CN701) and the SERVO board
(CN401) with the extension cable (Part No. J-2502-076-1).

NOTE FOR REPLACEMENT OF THE SERVO BOARD

When repairing, the complete SERVO board (Part No.
A-1555-002-A) should be replaced since any parts in the SERVO
board cannot be repaired.

NOTE FOR REPLACEMENT OF THE USB CONNECTOR
(CN902)

To replace the USB connector requires alignment.

1. Insert the USB connector into the front panel.

2. Place the KEY board on the front panel and align the terminals
of the USB connector with the holes in the KEY board.

3. Solder the four terminals of the connector.

NOTE FOR THE 20-PIN CONNECTOR (CN901)

Do not use alcohol to clean the 20-pin connector (CN901) connect­ing the front panel with the main body.
Do not touch the connector directly with your bare hand. Poor con­tact may be caused.

SERVO BOARD
CN401

MAIN BOARD
CN701

J-2502-076-1

KEY board

USB (socket) connector

front panel

CDX-GT49UM/GT490U/GT490US/GT494U

5

SECTION 2

GENERAL

This section is extracted
from instruction manual.

CONNECTIONS

• E, Indian, Mexican model

Ver. 1.1

Connection diagram

1 To a metal surface of the car

First connect the black ground (earth) lead, then connect the
yellow, and red power supply leads.

2 To the power antenna (aerial) control lead or power

supply lead of antenna (aerial) booster

Notes
t It is not necessar y to connect this lead if there is no power

antenna (aerial) or antenna (aerial) booster, or with a
manually-operated telescopic antenna (aerial).

t When your car has a built-in FM/AM antenna (aerial) in the

rear/side glass, see “Notes on the control and power supply
leads.”

3

system may damage the unit.

4 To the +12 V power terminal which is energized in

the accessory position of the ignition key switch

Notes
t If there is no accessory position, connec t to the +12 V power

(battery) terminal which is energized at all times.

Be sure to connect the black ground (earth) lead to a metal

t When your car has a built-in FM/AM antenna (aerial) in the

rear/side glass, see “Notes on the control and power supply
leads.”

5 To the +12 V power terminal which is energized at

all times

Be sure to connect the black ground (earth) lead to a metal

Notes on the control and power supply leads
t The power antenna (aerial) control lead (blue) supplies +12 V DC

when you turn on the tuner.

t When your car has built-in FM/AM antenna (aerial) in the rear/side

glass, connect the power antenna (aerial) control lead (blue) or the
accessory power supply lead (red) to the power terminal of the
existing antenna (aerial) booster. For details, consult your dealer.

t A power antenna (aerial) without a relay box cannot be used with

this unit.

Memory hold connection
When the yellow power input lead is connected, power will always
be supplied to the memory circuit even when the ignition switch is

Notes on speaker connection

t
t Use speakers with an impedance of 4 to 8 ohms, and with

adequate power handling capacities to avoid its damage.

t Do not connect the speaker terminals to the car chassis, or connect

the terminals of the right speakers with those of the left speaker.

t Do not connect the ground (earth) lead of this unit to the negative

(–) terminal of the speaker.

t Do not attempt to connect the speakers in parallel.
t Connect only passive speakers. Connecting active speakers (with

t To avoid a malfunction, do not use the built-in speaker leads

installed in your car if the unit shares a common negative (–) lead
for the right and left speakers.

t Do not connect the unit’s speaker leads to each other.

Note on connection

appears in the display. In this case, make sure the speaker and

Diagrama de conexión

1

Conecte primero el cable de conexión a masa negro, y después
los cables amarillo y rojo de fuente de alimentación.

2 Al cable de control de la antena motorizada o al

de señal de la antena

Notas
t

de antena, o se utiliza una antena telescópica accionada
manualmente, no será necesario conectar este cable.

t Si el automóvil incorpora una antena de FM/AM en el cristal

trasero o lateral, consulte “Notas sobre los cables de control y
de fuente de alimentación”.

3

opcional

cualquier otro sistema puede dañar la unidad.

4 Al terminal de alimentación de +12 V que recibe

energía en la posición de accesorio del interruptor
de encendido

Notas
t Si no hay posición de accesorio, conéctelo al terminal de

alimentación (batería) de +12 V que recibe energía sin
interrupción.

Asegúrese de conectar primero el cable de conexión a masa

t Si el automóvil incorpora una antena de FM/AM en el cristal

trasero o lateral, consulte “Notas sobre los cables de control y
de fuente de alimentación”.

5

Al terminal de alimentación de +12 V que recibe

energía sin interrupción

Asegúrese de conectar primero el cable de conexión a masa

Notas sobre los cables de control y de fuente de alimentación
t El cable de control de la antena motorizada (azul) suministrará cc

de + 12 V cuando conecte la alimentación del sintonizador.

t Si el automóvil dispone de una antena de FM/AM incorporada en

el cristal trasero o lateral, conecte el cable de control de antena
motorizada (azul) o el cable de fuente de alimentación auxiliar

existente. Para obtener más información, consulte a su distribuidor.

t Con esta unidad no es posible utilizar una antena motorizada sin

caja de relé.

Conexión para protección de la memoria
Si conecta el cable de fuente de alimentación amarillo, el circuito
de la memoria recibirá siempre alimentación, aunque apague el
interruptor de encendido.

Notas sobre la conexión de los altavoces
t Antes de conectar los altavoces, desconecte la alimentación de la

unidad.

t Utilice altavoces con una impedancia de 4 a 8 : con la capacidad

de potencia adecuada para evitar que se dañen.

t No conecte los terminales de altavoz al chasis del automóvil, ni

conecte los terminales del altavoz derecho con los del izquierdo.

t No conecte el cable de conexión a masa de esta unidad al terminal

negativo (–) del altavoz.

t No intente conectar los altavoces en paralelo.
t Conecte solamente altavoces pasivos. Si conecta altavoces activos

puede dañar la unidad.

t Para evitar fallas de funcionamiento, no utilice los cables de altavoz

incorporados instalados en el automóvil si la unidad comparte un
cable negativo común (–) para los altavoces derecho e izquierdo.

t No conecte los cables de altavoz de la unidad entre sí.

Nota sobre la conexión

aparecerá “FAILURE” en la pantalla. Si es así, compruebe la conexión
de ambos dispositivos.

2

4

5

1

3

L

R

REAR/SUB

AUDIO OUT

FRONT

REMOTE

IN

*

3

REAR/SUB

AUDIO OUT

*

2

FRONT

AUDIO OUT



AMP REM
Max. supply current 0.3 A

Corriente máx. de alimentación de 0,3 A

Fuse (10 A)
Fusible (10 A)

Blue/white striped
Con rayas azules y blancas

Red
Rojo

Yellow
Amarillo

White
Blanco

Green
Verde

Purple
Morado

White/black striped
Con rayas blancas y negras

Gray/black striped
Con rayas grises y negras

Green/black striped
Con rayas verdes y negras

Gray
Gris

Left
Izquierdo

Right
Derecho

ANT REM

Black
Negro

Blue
Azul

Max. supply current 0.1 A
Corriente máx. de alimentación de 0,1 A

Purple/black striped
Con rayas moradas y negras

*

1

from car antenna (aerial)
desde la antena del automóvil

Left
Izquierdo

Right
Derecho

*

1

*1 Cable con terminales RCA (no

suministrado)

*

2

AUDIO OUT (salida de audio) puede
cambiarse a SUB o REAR. Para obtener
información, consulte el manual de
instrucciones suministrado.

*

3

Puede requerirse un adaptador

independiente.

*

1

RCA pin cord (not supplied)

*

2

AUDIO OUT can be switched SUB or REAR.

For details, see the supplied Operating
Instructions.

*

3

Separate adaptor may be required.

CDX-GT49UM/GT490U/GT490US/GT494U

6

• Argentina model

Connection diagram

A

system may damage the unit.

Warning

If you have a power antenna (aerial) without a relay
box, connecting this unit with the supplied power
connecting lead 2 may damage the antenna (aerial).

Notes on the control and power supply leads
t The power antenna (aerial) control lead (blue) supplies +12 V DC

when you turn on the tuner.

t When your car has built-in FM/AM antenna (aerial) in the rear/side

glass, connect the power antenna (aerial) control lead (blue) or the
accessory power supply lead (red) to the power terminal of the
existing antenna (aerial) booster. For details, consult your dealer.

t A power antenna (aerial) without a relay box cannot be used with

this unit.

Memory hold connection
When the yellow power input lead is connected, power will always
be supplied to the memory circuit even when the ignition switch is

Notes on speaker connection

t
t Use speakers with an impedance of 4 to 8 ohms, and with

adequate power handling capacities to avoid its damage.

t Do not connect the speaker terminals to the car chassis, or connect

the terminals of the right speakers with those of the left speaker.

t Do not connect the ground (earth) lead of this unit to the negative

(–) terminal of the speaker.

t Do not attempt to connect the speakers in parallel.
t Connect only passive speakers. Connecting active speakers (with

t To avoid a malfunction, do not use the built-in speaker leads

installed in your car if the unit shares a common negative (–) lead
for the right and left speakers.

t Do not connect the unit’s speaker leads to each other.

Note on connection

appears in the display. In this case, make sure the speaker and

Diagrama de conexión

A

opcional

cualquier otro sistema puede dañar la unidad.

Advertencia

Si la antena motorizada no dispone de caja de relé,
es posible que la conexión de esta unidad mediante
el cable de alimentación suministrado 2 provoque
daños en la antena.

Notas sobre los cables de control y de fuente de alimentación
t El cable de control de la antena motorizada (azul) suministrará cc

de + 12 V cuando conecte la alimentación del sintonizador.

t Si el automóvil dispone de una antena de FM/AM incorporada en

el cristal trasero o lateral, conecte el cable de control de antena
motorizada (azul) o el cable de fuente de alimentación auxiliar

existente. Para obtener más información, consulte a su distribuidor.

t Con esta unidad no es posible utilizar una antena motorizada sin

caja de relé.

Conexión para protección de la memoria
Si conecta el cable de fuente de alimentación amarillo, el circuito
de la memoria recibirá siempre alimentación, aunque apague el
interruptor de encendido.

Notas sobre la conexión de los altavoces
t Antes de conectar los altavoces, desconecte la alimentación de la

unidad.

t Utilice altavoces con una impedancia de 4 a 8 : con la capacidad

de potencia adecuada para evitar que se dañen.

t No conecte los terminales de altavoz al chasis del automóvil, ni

conecte los terminales del altavoz derecho con los del izquierdo.

t No conecte el cable de conexión a masa de esta unidad al terminal

negativo (–) del altavoz.

t No intente conectar los altavoces en paralelo.
t Conecte solamente altavoces pasivos. Si conecta altavoces activos

puede dañar la unidad.

t Para evitar fallas de funcionamiento, no utilice los cables de altavoz

incorporados instalados en el automóvil si la unidad comparte un
cable negativo común (–) para los altavoces derecho e izquierdo.

t No conecte los cables de altavoz de la unidad entre sí.

Nota sobre la conexión

aparecerá “FAILURE” en la pantalla. Si es así, compruebe la conexión
de ambos dispositivos.

L

R

REAR/SUB FRONT

AUDIO OUT

A

REMOTE

IN

*

4

13 57

24 68

57

48

FRONT

AUDIO OUT

REAR/SUB

AUDIO OUT

*

3

2

AMP REM

Max. supply current 0.3 A
Corriente máx. de alimentación de 0,3 A

Fuse (10 A)
Fusible (10 A)

Blue/white striped
Con rayas azules y blancas

*

2

*1 from car antenna (aerial)
desde la antena del automóvil

*1 Nota sobre la conexión de la antena

Si la antena del automóvil es del tipo ISO (International
Organization for Standardization), emplee el adaptador
suministrado 8 para conectarla. En primer lugar, conecte la
antena del automóvil al adaptador suministrado y, a continuación,
a la toma de antena de la unidad principal.

*

2

Cable con terminales RCA (no suministrado)

*

3

AUDIO OUT (salida de audio) puede cambiarse a SUB o REAR.
Para obtener información, consulte el manual de instrucciones
suministrado.

*

4

Puede requerirse un adaptador independiente.

*

1

Note for the antenna (aerial) connecting

If your car antenna (aerial) is an ISO (International Organisation
for Standardisation) type, use the supplied adaptor 8 to connect
it. First connect the car antenna (aerial) to the supplied adaptor,
then connect it to the antenna (aerial) jack of the master unit.

*

2

RCA pin cord (not supplied)

*

3

AUDIO OUT can be switched SUB or REAR. For details, see the

supplied Operating Instructions.

*

4

Separate adaptor may be required.

See “Power connection diagram” on the reverse side
for details.

Para obtener más información, consulte el “Diagrama
de conexión de la alimentación” que encontrará al
dorso.

from the car’s power connector
desde un conector de alimentación
auxiliar del automóvil

from the car’s speaker connector
desde un conector de altavoces del
automóvil

Negative polarity positions 2, 4, 6, and 8 have striped leads.
Los cables de las posiciones de polaridad negativa 2, 4, 6 y 8 son
rayados.

Positions 1, 2, 3 and 6 do not have pins.
Las posiciones 1, 2, 3 y 6 no tienen pines.

4

Yellow

Amarillo

continuous power supply

fuente de alimentación continua

5

Blue
Azul

power antenna (aerial) control

control de la antena motorizada

7

Red
Rojo

switched power supply

fuente de alimentación conmutada

1

Purple

Morado

+

Speaker, Rear, Right

Altavoz, posterior, derecho

2–

Speaker, Rear, Right

Altavoz, posterior, derecho

3

Gray

Gris

+

Speaker, Front, Right

Altavoz, frontal, derecho

4–

Speaker, Front, Right

Altavoz, frontal, derecho

5

White
Blanco

+

Speaker, Front, Left

Altavoz, frontal, izquierdo

6–

Speaker, Front, Left

Altavoz, frontal, izquierdo

8

*

2

CDX-GT49UM/GT490U/GT490US/GT494U

7

• Saudi Arabia model

Connection diagram

1 To a metal surface of the car

First connect the black ground (earth) lead, then
connect the yellow, and red power supply leads.

2 To the power antenna (aerial) control lead

or power supply lead of antenna (aerial)
booster

Notes
t It is not necessary to connect this lead if there

is no power antenna (aerial) or antenna (aerial)
booster, or with a manually-operated telescopic
antenna (aerial).

t When your car has a built-in FM/AM antenna (aerial)

in the rear/side glass, see “Notes on the control
and power supply leads.”

3 To AMP REMOTE IN of an optional power

other system may damage the unit.

4 To the +12 V power terminal which is

energized in the accessory position of the
ignition key switch

Notes
t If there is no accessory position, connect to the

+12 V power (battery) terminal which is energized
at all times.

Be sure to connect the black ground (earth) lead to

t When your car has a built-in FM/AM antenna (aerial)

in the rear/side glass, see “Notes on the control
and power supply leads.”

5 To the +12 V power terminal which is

energized at all times

Be sure to connect the black ground (earth) lead to a

Notes on the control and power supply leads
t The power antenna (aerial) control lead (blue) supplies

+12 V DC when you turn on the tuner.

t When your car has built-in FM/AM antenna (aerial) in

the rear/side glass, connect the power antenna (aerial)
control lead (blue) or the accessory power supply lead
(red) to the power terminal of the existing antenna
(aerial) booster. For details, consult your dealer.

t A power antenna (aerial) without a relay box cannot be

used with this unit.

Memory hold connection
When the yellow power supply lead is connected, power
will always be supplied to the memory circuit even when
the ignition switch is turned o.

Notes on speaker connection

t Before connecting the speakers, turn the unit o.
t Use speakers with an impedance of 4 to 8 ohms, and with

adequate power handling capacities to avoid its damage.

t Do not connect the speaker terminals to the car

chassis, or connect the terminals of the right speakers
with those of the left speaker.

t Do not connect the ground (earth) lead of this unit to

the negative (–) terminal of the speaker.

t Do not attempt to connect the speakers in parallel.
t Connect only passive speakers. Connecting active

terminals may damage the unit.

t To avoid a malfunction, do not use the built-in speaker

leads installed in your car if the unit shares a common
negative (–) lead for the right and left speakers.

t Do not connect the unit’s speaker leads to each other.

Note on connection

“FAILURE” appears in the display. In this case, make

CDX-GT49UM/GT490U/GT490US/GT494U

8

SECTION 3

DISASSEMBLY

• This set can be disassembled in the order shown below.

3-1. SUB PANEL ASSY
(Page 9)

3-2. CD MECHANISM BLOCK
(Page 9)

SET

3-3. MAIN BOARD
(Page 10)

3-5. CHASSIS (T) SUB ASSY
(Page 11)

3-6. ROLLER ARM ASSY
(Page 11)

3-7. CHASSIS (OP) ASSY
(Page 12)

3-8. CHUCKING ARM SUB ASSY
(Page 12)

3-9. SLED MOTOR ASSY
(Page 13)

3-10. OPTICAL PICK-UP SECTION
(Page 14)

3-11. OPTICAL PICK-UP
(Page 14)

3-4. SERVO BOARD
(Page 10)

CDX-GT49UM/GT490U/GT490US/GT494U

9

Note:

Follow the disassembly procedure in the numerical order shown below.

3-1. SUB PANEL ASSY

3-2. CD MECHANISM BLOCK

2 two claws

3 two claws

4 sub panel assy

1 two screws

(+PTT 2.6 u 6)

4 CN701

3

1

screw

(+PTT 2.6

u

6)

2

screw

(+PTT 2.6

u

6)

6 two

screws

(+PTT 2.6

u

4)

7 bracket (CD)

8 CD mechanism block

5 CN501 (3P)

CDX-GT49UM/GT490U/GT490US/GT494U

10

3-3. MAIN BOARD

3-4. SERVO BOARD

9 MAIN board

insulating sheet

3

2 two

screws

(+PTT 2.6

u

8)

1 three

screws

(+BTT 2.6

u

5)

7

screw

(+PTT 2.6

u

10)

8 heat sink

4 two

screws

(+P 2.6

u

8)

6

screw

(+P 2.6

u

8)

5 two

screws

(+PTT 2.6

u

10)

7 SERVO board

SERVO board

3 toothed lock screw
(M 1.7 u 2.5)

2 toothed lock screw
(M 1.7 u 2.5)

1 Remove the eleven solders.

6 optical pick-up (16 core)

(CN101)

4 claw

5 claw

gray

yellow

blue

orange

red

black

red

white

black

red

white

CDX-GT49UM/GT490U/GT490US/GT494U

11

3-5. CHASSIS (T) SUB ASSY

3-6. ROLLER ARM ASSY

4 chassis (T) sub assy

3 claw

1 two screws

(M 1.7 u 2.5)

2 two screws
(M 1.7 u 2.5)

3 washer

4 gear (RA1)

6 roller arm assy

5

1 spring (RAL)

2 spring (RAR)

CDX-GT49UM/GT490U/GT490US/GT494U

12

3-7. CHASSIS (OP) ASSY

3-8. CHUCKING ARM SUB ASSY

7 two coil springs (damper) (natural)

8 coil spring (damper) (green)

6 chassis (OP) assy

5

1

tension spring (KF)

2 gear (LE1)

3 lever (D)

4 slider (R)

3 chucking arm sub assy

2

1 spring

Note: Have this portion receive the chassis.

Note: Have this portion receive the chassis.

Note: Be careful not to touch the turn table.