Sony HCD-DX375 Service Manual Download Page 4

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HCD-DX375

SECTION 1

SERVICING NOTE

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 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,
observe from more than 30 cm away from the objective lens.

LASER DIODE AND FOCUS SEARCH

1. Open the cover and turn POWER on with no disc inserted.
2. Confirm that the following operation is performed while

observing the objecting lens.
1)

Confirm that laser beam is spread.

Up and down motion of the objective lens. (3 times)

DISC TRAY LOCK

The disc tray lock function for the antitheft of an demonstration
disc in the store is equipped.

Setting Procedure :

1. Press the

?/1

button to turn the set on.

2. Press the

[FUNCTION]

button to set DVD function.

3. Insert a disc.
4. Press the

button and the

button simultaneously for five

seconds.

5. The message “LOCKED” is displayed and the tray is locked.

Releasing Procedure :

1. Press the

button and the

button simultaneously for five

seconds again.

2. The message “UNLOCKED” is displayed and the tray is

unlocked.

Note 1:

When “LOCKED” is displayed, the tray lock is not released by
turning power on/off with the

?/1

button.

Note 2:

Incorrect operations may be performed if the test mode ia not
entered properly.
In this case, press the

?/1

button to turn the power off, and

retry to enter the test mode.

Note 3:

If the disc tray does not open and the message “LOCKED”
appears, press the

button and the

button simultaneously

for seconds or longer.
Then remove your fingers from the above stick and the button.
The message “UNLOCKED” appears for 2 seconds and the disc
tray opens.

Note on DMB12 board replacement

New part of EEP ROM (IC103, IC706) on the DMB12 board cannot be
used. Therefore, if the mounted DMB12 board (A-1148-813-A) is replaced,
exchange new EEP ROM (IC103, IC706) with that used before the

replacement.

When the self-diagnosis function is activated to
prevent the system from malfunctioning, a 5-
character service number (e.g., C 13 50) with a
combination of a letter and 4 digits appears on
the screen and the front panel display. In this
case, check the following table.

When displaying the version
number on the screen

When you turn on the system, the version
number [VER.X.XX] (X is a number) may
appear on the screen. Although this is not a
malfunction and for Sony service use only,
normal system operation will not be possible.
Turn off the system, and then turn on the system
again to operate.

Self-diagnosis Function

(When letters/numbers appear in the
display)

First 3
characters of
the service
number

Cause and/or corrective action

C 13

The disc is dirty.

Clean the disc with a soft cloth

C 31

The disc is not inserted correctly.

Restart the system, then re-insert
the disc correctly.

E XX

(xx is a number)