HCD-EC68, HCD-EC78, MHC-EC68, MHC-EC78 - Sony Audio Service Manual (repair manual). Page 16

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 [

I/1

] button to turn the power on.

2.  Press three buttons of [CD N], [TUNING + M L], and  

DISPLAY simultaneously.

3.  Press the [FUNCTION] button to select CD function.
4.  It enters the CD service mode and displays “SERVICE”.
5.  To exit from this mode, press three buttons of [CD N], [TUN-

ING + M L]  and  DISPLAY  simultaneously.

Key Operation:
[TUNING + M L], [l m – TUNING]: 
 

Use these keys to move the SLED. When [TUN-
ING + 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. 

[DISPLAY]: 
 

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 CD mechanism (CDM) are displayed as the 
CDM Errors, and those of the optical pick-up system (= optical 
unit + CD board) are displayed as the BD Errors as shown below. 
Procedure:
1.   Press the [

I/1

] button to turn the power on.

2.   Press the [FUNCTION] button to select CD function.
3.  Press three buttons of [TUNING + M L], [

x

] and [DIS-

PLAY] simultaneously.

4.  Then, the CDM error code is displayed as “M0xxxxxx” (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 “M” starting from “M0” up 
to “M9”, and then returns to “M0”. Every pressing of the [l 
m

 – TUNING] button in this mode decrements the number 

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

6.  When the [PLAY MODE/TUNING MODE] button is pressed 

then, the BD error code is displayed as “D0xxxxxx” (x means 
hexadecimal number) on the liquid crystal display as shown 
below. In the same way as the CDM error code, use of the 
[TUNING + M L] and the [l m – TUNING] but-
tons in this mode enables tracing of the error history. 

7.  To release from this mode, press the [

I/1

] button to turn the 

power off.

Contents of “CDM Errors”
Error display example
 

M 0  FF 11 42

 

  1  2  3  4

1

  It indicates the error history number

 

0 to 9: The error code number 0 indicates the newest error.

2

  It indicates whether the CDM error occurs in the normal opera-

tions or during the initialization operation. 
FF 

: The error has occurred in the normal opera-

tions. 

Other than FF :  The error has occurred during the initialization 

operation.

3

  It indicates the processing during which the trouble has oc-

curred.
01: The disc EJECT processing is in progress.
02: The disc INSERTION-WAITING processing is in prog-

ress.

03: Processing of the disc INSERTION-REQUEST for the up-

per CD tray is in progress.

04: Processing of the disc EJECTION-REQUEST for the up-

per CD tray is in progress. 

05: The disc pulling-in operation is in progress.
06: The disc chucking processing is in progress.
07:  The disc re-chucking processing is in progress.
08: The disc chucking-release completion operation is in prog-

ress.

4

 It indicates the operation during which the trouble has oc-

curred.
00 

: Waiting for the operation.

10 to 13 : The disc EJECT operation is in progress.
20 

: The disc pulling-in operation is in progress.

30 

: The disc chucking-release operation is in progress.

40 to 43 :  The disc EJECT operation due to error is in prog-

ress.

Contents of “BD Errors”  
Error display example
 

D  0  02 09 01

 

  1  2  3  4

1

  It indicates the error history number

 

0 to 9: 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