DOWNLOAD Sony HCD-H991AV / MHC-991AV / MHC-G99AV Service Manual ↓ Size: 871.8 KB | Pages: 60 in PDF or view online for FREE

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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.

Press ENTER/NEXT button and POWER button simultaneously
to switch the AM channel step 9 KHz and 10 KHz. Be sure not to
change with carelessness.

When the AMS dial is rotated in the clockwise direction, the count
increases in the following order.
J1 

n J2 n J3.

When rotated in the counterclockwise direction, it decreases in the
following order.
J0 

n J9 n J8.

To exit form the test mode, press the TUNER/BAND , DISPLAY/
DEMO , MENU 2 buttons simultaneously again.

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.

When the TUNER/BAND , DISPLAY/DEMO , and MENU 2
buttons are pressed simultaneously, the FL display tube and LEDs
will all light up. Press any button to enter the key check mode.
When the key check mode is entered, the FL display tube displays
“K 1 J0 V0”. Each time a button is pressed, the counter increases in
the following order, K 2 

n K 3 n K 4.

If buttons already pressed once are pressed again, the counter will
not increase. When the  VOLUME  knob is rotated in the + direction,
the count increases in the following order.
V1 

n V2 n V3.

When rotated in the – direction, it decreases in the following order.
V0 

n V9 n V8.

1 Remove the Case

3 Pull-out the disc tray

2 Turn the cam to the

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(US, Canadian, AEP, UK, German,
Italian, Malaysia, Australian,
Thailand models)

(E, Saudi Arabia, Hong Kong,  Singapore,
Argentine, Indonesian, PX models)

*AMS = Automatic Music Sensor.

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1 Turn the cam to the

2 Pull-out the disc tray

3 Loading panel

2 Two screws

4 Screw

5 Screw

6 Three claws

7 Front panel

3 Two screws

1 Remove the connectors

Note: Follow the disassembly procedure in the numerical order given.