DOWNLOAD Sony CMT-EH45DAB / HCD-EH45DAB Service Manual ↓ Size: 3.29 MB | Pages: 38 in PDF or view online for FREE

The cold reset clears all data including preset data stored in the 
memory to initial conditions. Execute this mode when returning 
the set to the customer.
Procedure:
1.  Press three buttons of [

x

], [

l

 

m

 – TUNING] and [

?/1

] 

simultaneously.

2.  When “RESET” appears, the set enters standby status.

Procedure:
1.  Press the [

?/1

] button to turn the power on.

2.  Press three buttons of [FUNCTION], [TUNER/BAND], and 

[

?/1

] simultaneously.

3.  When the panel test is activated, [STANDBY] LED and seg-

ments on the liquid crystal display are all turned on.

4.  Press the [CD 

u

] button, date and version are displayed. For 

example, “1029V001”.

5.  Press the [TUNER/BAND] button, model name and destination 

are displayed. For example, “EH45CE2”.

6.  To release from this mode, press three buttons of [FUNCTION], 

[TUNER/BAND], and [

?/1

] simultaneously.

This mode can move the SLED of the optical pick-up, and also can 
turn the optical pick-up laser power on and off.
Procedure:
1.  Press the [

?/1

] button to turn the power on.

2.  Press the [FUNCTION] button to select CD function.
3.  Press three buttons of [

l

 

m

 – TUNING], [FUNCTION], 

and [

?/1

] simultaneously.

4.  It enters the CD service mode and displays “SERVICE”.
5.  To release from this mode, press three buttons of [

l

 

m

 

– TUNING], [FUNCTION]  and [

?/1

] simultaneously.

Key Operation:
[TUNING + 

M

 

L

], [

l

 

m

 – TUNING]: 

 

Use these keys to move the SLED. When [TUNING 
+ 

M

 

L

] is pressed in this mode, the SLED moves 

to outer circumference and the message “SLED 
OUT” is displayed.

 When 

[

l

 

m

 – TUNING] is pressed in this 

mode, the SLED moves to inner circumference and 
the message “SLED IN” is displayed. 

[FUNCTION]: 
 

Use this key to turn the optical pick-up laser power 
on and off. When the laser power is turned on, the 
message “LD ON” is displayed. When the laser 
power is turned off, the message “LD OFF” is dis-
played. 

The past errors of the optical pick-up system (= optical unit + CD 
board) are displayed as the BD Errors as shown below. 
Procedure:
1.   Press the [

?/1

] button to turn the power on.

2.   Press the [FUNCTION] button to select CD function.
3.  Press three buttons of [

l

 

m

 – TUNING], [DSGX] and 

[

?/1

] simultaneously.

4.  Then, the BD error code is displayed as “D0xxxxxx” (x means 

hexadecimal number) on the liquid crystal display as shown 
below. 

5.  Every pressing of the [TUNING + 

M

 

L

] button in this 

mode increments the number after “D” starting from “D0” up 
to “D4”, and then returns to “D0”. Every pressing of the [

l

 

m

 – TUNING] button in this mode decrements the number 

after “D”. The smaller the error code number is, the newer the 
error content is. 

6.  To release from this mode, press the [

?/1

] button to turn the 

power off.

Contents of “BD Errors”  
Error display example
 

D  0  01 06 01

 

  1  2  3  4

1

  It indicates the error history number

 

0 to 4: The error code number 0 indicates the newest error.

2

  It indicates the error content

01: The focus servo cannot lock-in. 
02: GFS is no good (NG).
03: The startup time exceeds the specifi ed period of time (time 

over)

04:  The focus servo is unlocked continuously. 
05:  Q code cannot be obtained within the specifi ed period of 

time.

06: The tracking servo cannot lock-in.
07: Blank disc

 
3

  It indicates the on-going processing of optical pick-up system 

(= optical unit + CD board) when the trouble has occurred.
01:   The CD SHIP mode processing is in progress.
02:   The POWER OFF processing is in progress.
03:  The POWER ON processing is in progress.
04:   The INITIALIZE processing is in progress.
05:   The optical pick-up system (= optical unit + CD board) is 

in the stop state. 

06:   The STOP operation is in progress.
07:   The startup processing is in progress.
08:   The TOC read-in processing is in progress.
09:   The SEARCH operation is in progress.
0A:  The PLAY operation is in progress.
0B:  The PAUSE operation is in progress.
0C:  The PLAY – MANUAL SEARCH operation is in prog-

ress.

0D:  The PAUSE – MANUAL SEARCH operation is in prog-

ress.

4

  It indicates the operation that is being processed when the trou-

ble has occurred.

 

It indicates the step number of each processing specifi ed by 3. 
Because the numbers of steps are different in each processing, 
this number is different in each processing.

PRECAUTION
1.  Clean the following parts with a denatured-alcohol-moistened
 swab:
 

   record/playback head 

pinch roller

 

   erase head 

rubber belts

 

   capstan 

idlers

2.  Demagnetize the record/playback head with a head demag-

netizer. (Do not bring the head magnetizer close to the erase 
head.)

3.  Do not use a magnetized screwdriver for the adjustments.
4.  After the adjustments, appiy suitable locking compound to the 

parts adjusted.

5.  The adjustments should be performed with the rated power 

supply voltage unless otherwise noted.

FWD

CQ-102AS

2.0 – 8.0 mN • m

(20 – 80 g • cm)

(0.28 – 1.12 oz • inch)

FWD 
Back Tension

CQ-102C

0.15 – 0.6 mN • m

(1.5 – 6.0 g • cm)

(0.021 – 0.083 oz • inch)

FF

CQ-201AS

5.0 – 17.7 mN • m

(50 – 177 g • cm)

(0.7 – 2.48 oz • inch)

REW

CQ-201B

5.0 – 17.7 mN • m

(50 – 177 g • cm)

(0.7 – 2.48 oz • inch)

FWD

CQ-403A

more than 80 g

(more than 2.82 oz)

DECK SECTION      0 dB = 0.775 V

1.  Demagnetize the record/playback head with a head
 demagnetizer. 
2.  Do not use a magnetized screwdriver for the adjustments.

P-4-A063

6.3 kHz, –10 dB

Azimuth Adjustment

Procedure:
1. Mode: 

Playback

2.  Turn the adjustment screw and check output peaks. If the peaks 

do not match for L-CH and R-CH, turn the adjustment screw 
so that outputs match within 1dB of peak.

3. Mode: 

Playback

°

° 135° 180°

4.  After the adjustments, apply suitable locking compound to the 

pats adjusted.

Adjustment Location: Record/Playback/Erase Head

Note:  Remove the cassette lid before this adjustment.
 

Refer to “DISASSEMBLY” (page 6)

TUNER SECTION     

Procedure:
1.  Turn on the set.
2.  Input the following signal from signal generator to FM antenna 

input directly.

Carrier frequency  : A = 87.5 MHz, B = 98 MHz, C = 108 MHz
Deviation  

:75  kHz

Modulation 

: 1 kHz

ANT input 

: 35 dBu (EMF)

Note:  Use 75 ohm coaxial cable to connect signal generator and the set. 

You cannot use video cable for checking.

 

Use signal generator whose output impedance is 75 ohm. 

3.  Set to FM tuner function and tune A, B and C signals.
4. Confi rm “TUNED” is lit on the display for A, B and C sig-

nals.

When the selected station signal is received in good condition, 
“TUNED” is displayed.

1.  CD Block is basically constructed to operate without adjust-

ment.

2.  Use YEDS-18 disc (3-702-101-01) unless otherwise indicat-

ed.

3.  Use an oscilloscope with more than 10 M

Ω impedance.

4.  Clean the object lens by an applicator with neutral detergent 

when the signal level is low than specifi ed value with the fol-
lowing checks.

5.  Check the focus bias check when optical pick-up block is re-

placed.

Procedure:
1.  Connect oscilloscope to TP122 (RFEQO) and TP124 (VC) on 

the CD board.

2.  Press the [

?

/

1

] button to turn the power on.

3.  Set the disc (YEDS-18) and press the [CD 

u

] button to play-

back.

4. Confi rm that oscilloscope waveform is as shown in the fi gure 

below. (eye pattern)

 

A good eye pattern means that the diamond shape (

◊) in the 

center of the waveform can be clearly distinguished.