CDX-A251C - Sony Car Audio Service Manual (repair manual)

Model
CDX-A251C
Pages
51
Size
5.02 MB
Type
PDF
Document
Service Manual
Brand
Device
Car Audio
File
cdx-a251c.pdf
Date

View Sony CDX-A251C Service Manual online

1
Ver. 1.0  2006. 01
Model Name Using Similar Mechanism
CDX-GT50W/GT500/GT550
CD Drive Mechanism Type
MG-611WA-186//Q
Optical Pick-up Name
KSS1000E
SERVICE MANUAL
US Model
Canadian Model
AEP Model
UK Model
E Model
CDX-A251C
SPECIFICATIONS
• The tuner and CD sections have no adjustments.
Sony Corporation
eVehicle Division
Published by Sony Techno Create Corporation
9-887-047-01
2006A04-1
© 2006. 01
FM/MW/LW COMPACT DISC PLAYER
AEP,UK MODEL
FM/AM COMPACT DISC PLAYER
US, Canadian, E, Mexican MODEL
AUDIO POWER SPECIFICATIONS (US Model)
POWER OUTPUT AND TOTAL HARMONIC DISTORTION
23.2 watts per channel minimum continuous average power into
4 ohms, 4 channels driven from 20 Hz to 20 kHz with no more
than 5% total harmonic distortion.
CD Player section
Signal-to-noise ratio:
120 dB
Frequency response:
10 – 20,000 Hz
Wow and flutter:
Below measurable limit
Tuner section
FM
Tuning range:
US, CND model:
87.5 – 107.9 MHz
AEP, UK model:
87.5 – 108.0 MHz
E, MX model:
87.5 – 108.0 MHz (at 50 kHz step)
87.5 – 107.9 MHz (at 200 kHz step)
FM tuning interval:
E, MX model:
50 kHz/200 kHz switchable
Antenna terminal:
External antenna connector
Intermediate frequency:
10.7 MHz/450 kHz
Usable sensitivity:
9 dBf
Selectivity:
75 dB at 400 kHz
Signal-to-noise ratio:
67 dB (stereo), 69 dB (mono)
Harmonic distortion at 1 kHz:
0.5 % (stereo), 0.3 % (mono)
Separation:
35 dB at 1 kHz
Frequency response:
30 – 15,000 Hz
AM (US, CND, E, MX)
Tuning range:
US, CND model:
530 – 1,710 kHz
E, MX model:
531 – 1,602 kHz (at 9 kHz step)
530 – 1,710 kHz (at 10 kHz step)
AM tuning interval:
E, MX model:
9 kHz/10 kHz switchable
Antenna terminal:
External antenna connector
Intermediate frequency:
10.7 MHz/450 kHz
Sensitivity:
30 µV
MW/LW (AEP, UK)
Tuning range:
MW: 531 – 1,602 kHz
LW: 153 – 279 kHz
Aerial terminal:
External aerial connector
Intermediate frequency:
10.7 MHz/450 kHz
Sensitivity:
MW: 30 µV, LW: 40 µV
– Continued on next page –
Photo: AEP, UK model
2
CDX-A251C
If the optical pick-up block is defective, please replace the whole
optical pick-up block.
Never turn the semi-fixed resistor located at the side of optical
pick-up block.
NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK
OR BASE UNIT
The laser diode in the optical pick-up block may suffer electrostatic
breakdown because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic breakdown and also use
the procedure in the printed matter which is included in the repair
parts.
The flexible 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 reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission, ob-
serve from more than 30 cm away from the objective lens.
Notes on Chip Component Replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
SERVICE NOTES
This label is located on the bottom of the chassis.
TEST DISCS
This set can playback CD-R and CD-ROM discs. The following
test discs should be used to check the capability:
CD-R test disc TCD-R082LMT (Part No. J-2502-063-1)
CD-RW test disc TCD-W082L (Part No. J-2502-063-2)
optical pick-up
semi-fixed resistor
CAUTION
Use of controls or adjustments or performance of procedures other
than those specified herein may result in hazardous radiation
exposure.
This compact disc player is classified as a CLASS 1 LASER
product. The CLASS 1 LASER PRODUCT label is located on the
exterior.
AEP, UK, E, MX Model:
Power amplifier section
Outputs:
Speaker outputs (sure seal connectors)
Speaker impedance:
4 – 8 ohms
Maximum power output: US, CND, E, MX model:
52 W 
×
 4 (at 4 ohms)
AEP, UK model:
50 W 
×
 4 (at 4 ohms)
General
Outputs:
Audio outputs terminal (sub/rear switchable)
Power antenna relay control terminal
Power amplifier control terminal
Inputs:
Telephone ATT control terminal (AEP, UK, E, MX)
BUS control input terminal
BUS audio input terminal
Remote control input terminal
Antenna input terminal
AUX input jack (stereo mini jack)
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)
Dimensions:
Approx. 178 
×
 50 
×
 178 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)
US and foreign patents licensed from Dolby Laboratories.
MPEG Layer-3 audio coding technology and patents licensed from
Fraunhofer IIS and Thomson.
Note
This unit cannot be connected to a digital preamplifier or an equalizer
which is Sony BUS system compatible.
Design and specifications are subject to change
without notice.
• Abbreviation
CND : Canadian model
MX : Mexican model
SAFETY-RELATED  COMPONENT  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.
ATTENTION AU COMPOSANT AYANT RAPPORT
 À LA SÉCURITÉ!!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE 
0
 SUR LES
DIAGRAMMES SCHÉMATIQUES ET LA LISTE  DES PIÈCES
SONT CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT.
NE REMPLACER CES COMPOSANTS QUE PAR DES PIÈCES
SONY DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL
OU DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.
3
CDX-A251C
z
 UNLEADED SOLDER
Boards requiring use of unleaded solder are printed with the lead
free 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 flow)
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.
SERVO BOARD
CN2
MAIN BOARD
CNP301
J-2502-076-1
EXTENSION CABLE AND SERVICE POSITION
When repairing or servicing this set, connect the jig (extension cable)
as shown below.
• Connect the MAIN board (CNP301) and the SERVO board (CN2)
with the extension cable (Part No. J-2502-076-1).
• CD playback
You can play CD-DA (also containing CD TEXT*), CD-R/CD-
RW (MP3/WMA files also containing Multi Session and ATRAC
CD (ATRAC3 and ATRAC3plus format).
Type of discs
Label on the disc
CD-DA
MP3
WMA
ATRAC CD
* A CD TEXT disc is a CD-DA that includes information such as
disc, artist and track name.
4
CDX-A251C
TABLE OF CONTENTS
1. GENERAL
Location of controls and basic operations ............................... 5
Connections ............................................................................. 7
2. DISASSEMBLY
2-1. Sub Panel Assy .................................................................. 10
2-2. CD Mechanism Block ....................................................... 11
2-3. Main Board ....................................................................... 11
2-4. Chassis (T) Sub Assy ........................................................ 12
2-5. Roller Arm Assy ................................................................ 12
2-6. Chassis (OP) Assy ............................................................. 13
2-7. Optical Pick-up ................................................................. 13
2-8. SL Motor Assy (M902) ..................................................... 14
2-9. LE Motor Assy (M903) ..................................................... 14
2-10. Servo Board ....................................................................... 15
3. DIAGRAMS
3-1. Circuit Boards Location .................................................... 16
3-2. Block Diagram – CD Section – ......................................... 17
3-3. Block Diagram – Main Section – ...................................... 18
3-4. Block Diagram – Display Section – .................................. 19
3-5. Printed Wiring Boards – CD Mechanism Section – ......... 21
3-6. Schematic Diagram – CD Mechanism Section (1/2) – ..... 22
3-7. Schematic Diagram – CD Mechanism Section (2/2) – ..... 23
3-8. Printed Wiring Board – Main Section – ............................ 24
3-9. Schematic Diagram – Main Section (1/4) – ...................... 25
3-10. Schematic Diagram – Main Section (2/4) – ...................... 26
3-11. Schematic Diagram – Main Section (3/4) – ...................... 27
3-12. Schematic Diagram – Main Section (4/4) – ...................... 28
3-13. Printed Wiring Boards – Key Section – ............................ 29
3-14. Schematic Diagram – Key Section – ................................ 30
4. EXPLODED VIEWS
4-1. Main Section ..................................................................... 38
4-2. Front Panel Section ........................................................... 39
4-3. CD Mechanism Section (1) ............................................... 40
4-4. CD Mechanism Section (2) ............................................... 41
4-5. CD Mechanism Section (3) ............................................... 42
4-6. CD Mechanism Section (4) ............................................... 43
5. ELECTRICAL PARTS LIST
........................................ 44

Download Sony CDX-A251C Service Manual (Repair Manual)

Here you can view online and download Sony CDX-A251C Service Manual in PDF. Usually contens schematics / circuit diagrams, wiring diagrams, block diagrams, printed wiring boards, exploded views, parts list, disassembly / assembly, pcb. This Service Manual can help you recover, restore, fix, disassemble and repair Sony CDX-A251C Car Audio.