DOWNLOAD Sony CDX-GT490U / CDX-GT490US / CDX-GT494U / CDX-GT49UM Service Manual ↓ Size: 2.27 MB | Pages: 40 in PDF or view online for FREE

Model
CDX-GT490U CDX-GT490US CDX-GT494U CDX-GT49UM
Pages
40
Size
2.27 MB
Type
PDF
Document
Service Manual
Brand
Device
Car Audio
File
cdx-gt490u-cdx-gt490us-cdx-gt494u-cdx-gt49um.pdf
Date

Sony CDX-GT490U / CDX-GT490US / CDX-GT494U / CDX-GT49UM Service Manual ▷ View online

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 off.
Notes on speaker connection
t   Before connecting the speakers, turn the unit off.
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
two claws
3 two claws
4 sub panel assy 
1 two screws
 (+PTT 
2.6 
u 6)
CN701
3
screw
 (+PTT 
2.6 
u 6)
screw
 (+PTT 
2.6 
u 6)
two screws
 (+PTT 
2.6 
u 4)
bracket (CD)
CD mechanism block
CN501 (3P)
CDX-GT49UM/GT490U/GT490US/GT494U
10
3-3.   MAIN  BOARD
3-4.   SERVO  BOARD
MAIN board 
insulating sheet
3
two screws
 (+PTT 
2.6 
u 8)
three screws
 (+BTT 
2.6 
u 5)
screw
 (+PTT 
2.6 
u 10)
heat sink
two screws
 (+P 
2.6 
u 8)
screw
 (+P 
2.6 
u 8)
two screws
 (+PTT 
2.6 
u 10)
SERVO board 
SERVO board 
toothed lock screw
 (M 
1.7 
u 2.5)
toothed lock screw
 (M 
1.7 
u 2.5)
Remove the eleven solders.
optical pick-up (16 core)
 (CN101)
claw
claw
gray
yellow
blue
orange
red
black
red
white
black
red
white
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