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<Disassembling and assembling procedure>
· Removing the tray (emergency ejection)

Removing the tray lock (set state)

VIDEO

Tray Decoration Panel

Insert a thin plate into the hatching part, slowly move the it in the arrow direction so that the tray is moved out a little in the arrow direction.

Note: In this state the tray cannot be removed completely.

· Drive Unit State

VIDEO

Tray Decoration Panel

Slowly move in the arrow direction, using the screwdriver having a fine head.

<Disassembling and assembling the mechanism chassis>
1. Remove the pickup FPC and loading relay FFC  A  from the main PWB.

Note: Fit the conductive rubber cap to the front end of pickup FPC (short-circuit).

2. Remove the solder joint of loading relay PWB at drive unit rear side.

1

Sled motor lead wire (Yellow·Orange)

2

IN SW lead wire 2 (White)

3

Spindle motor lead wire (Red·Black)

4

Loading motor lead wire (Red·Black)

5

Remove each lead wire from the claw.

1

1

2

3

4

3

2

4

A

B

C

SLmotor 1

SLmotor 2

SW

GND

SP1

SP2

L motor2

L motor2

Black

Red

Red

Black

White

White

Orange

Yellow

Remove the lead wire.

Remove the lead wire.

3. Remove the relay PWB mounting screw  B  (M2.6S + 6S S tight), and remove the relay PWB  C .

Relay PWB

Rear side of moving chassis assembly

Conductive rubber cap

(Earth sponge)

4. Disassembling the mechanism chassis moving chassis assembly

(1) Remove the four M2.6 screws  A  , and remove the clamped top plate  B .

P tight screw
with M2.6 washer

A

A

B

(2) Remove the M2.6 screw  C  .
(3) Holding aslant upward the mechanism chassis moving chassis assembly  D  in the arrow direction, remove.
Note: The slide rack  E  must be moved to the left side as shown in diagram.

Take care so that the lead wires, especially the earth sponge  G  at the pickup FPC   F  front end, must not beremoved.

Slide rack

Mechanism chassis moving
chassis assembly

P tight screw with
M2.6 washer

G

C

F

E

D

Clamper top
plate rear side

8. Replacing the Sled Motor

(1) At the rear side of chassis remove the two M1.7 screws  A  , and remove the motor angle  B  .
(2) Remove the thrust holding screw  C   (for easier removing wipe off the thread lock).
(3) Remove the two motor fitting screws M1.4  D  , and replace the motor  E  . Motor is replaced in the state while the worm  F  is

kept press-fitted to the output shaft.

Note: When installing the motor, take care so that the worm does not damage the ANG  B  hole.
(4) Screw in the thrust holding screw  C  , adjust the worm front end clearance to 0 to 0.1 mm, and apply screw lock.

5. Disassembling the loading drive system

(1) Remove the two M2 screws  A  .

(4)

Remove relay gear 2  E  .

(2) Remove the tray pinion  B  .

(5)

Remove the two M1.7 screws  F  .

(3) Remove the relay gear 1  C   together with the

(6)

Remove the L motor  G  (with pulley) downward.

timing belt S  D  .

M2

M1.7

L·Motor Pulley
L·Motor

Timing belt S

Relay
gear1

Relay
gear2

Tray pinion

A

B

E

C

D

G

F

6. Disassembling the mechanism chassis from the moving chassis

(1) Remove the insulator  B  (2 pcs. at the right side in diagram) parallel in the arrow direction.

(At this time it is better to insert the fine head of screw driver at the ID side of insulator and to move in the arrow direction, which
facilitates removal.)

(2) Remove the mechanism chassis in the arrow direction, pulling upward aslant.

At this time take care so that the insulator  C  (left side, 2 pcs.) is not damaged. (Do not put at once the mechanism chassis
assembly.)

Insulator

Insulator

Insulator

Insulator

Mechanism chassis

C

B

B

C

7. Replacing the pickup and the spindle motor
Since the pickup optical axis and turntable inclination of DVD are adjusted with higher accuracy than of CD/MD, make a replacement
as a mechanism service chassis ass'y (refer to Parts List).

Thrust holding screw

Apply screw-lock.

M1.4 screw

M1.7 screw

Motor Angle

B

A

D

Worm F

Sled motor E

C

Mecha chassis Ass'y

(1) Tray loading mechanism

When the tray loading motor rotates counterclockwise, motion is transmitted to the slide rack  D  through the intermediate

gear 1  A  , intermediate gear 2   B   and tray pinion  C  , resulting in insignificant motion in the arrow direction.

The slide rack is linked with the operating chassis. It lowers the pickup mechanism.

The protrusion of slide rack   E   is linked with the tray through the groove at the rear side of tray, so that the tray is

pushed ahead a little. When the tray is pushed out, the slide rack is disconnected from the tray pinion, and at the same

time the gear at the rear side of tray is connected with the tray pinion, and the tray is pushed ahead.

When the tray is pushed out fully, the slide rack moves further in the arrow direction through the groove at the rear side

of tray. The tray position detection switch  F  is turned on, and the tray loading motor stops.

When the tray closes the operation is as follows. If the tray OPEN/CLOSE button or tray is pressed and the detection

switch is turned off, the tray loading motor rotates clockwise, so that the tray is retracted. When the detection switch

is turned on again, the tray loading motor stops.

Intermediate gear 2

Intermediate gear 1

Tray pinion

Pawl linked with the groove at the 
rear side of tray

This groove is linked with the pawl of 
pickup mechanism.

Tray position detection switch

Slide rack

F

D

E

B

C

A

Sled motor

Pickup

Sled pinion

Rack

Pickup

Position detection

switch

Spindle motor

E

C

B

A

D

(2) Pickup feed mechanism

When the sled motor  A  rotates, the rack  C  moves through the sled pinion  B  so that the pickup  D  is moved to the

internal or external periphery.

When it is moved to the innermost periphery, the position detection switch   E    is pushed by the rack, so that the position

of pickup is initialized.

(3) Disc rotation mechanism

The spindle motor is used to rotate.

IC701 is used to control.

When the spindle motor is replaced, replace the

spindle unit.

The pickup unit reads signals from the disk, and the flexible cable is connected to the board. The following signals flow through the
cable.

FO+

TR–

TR+

FO–

ACTUATOR

OSC

V

OS

LD

PD

VA

VB

VC

VD

Sga

V

raf

V

cc

GND

–
+
–
+
–
+
–
+

HOLOGRAM LASER UNIT

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

1

TR–

FO+

TR+

FO–

VR

PD

V

CC

GND

LD

GND

V

OS

NC

NC

V

ref

(VCC/2)

VA

VC

Sga

GND

VB

VD

(NC)

Power adjust

HIGH-FREQUENCY CONVOLUTION

Focus

When electric current is flowed

FO+, FO-

from FO+ to FO-, the lens comes
 to near the disk.

Tracking

When electric current is flowed

TR+, TR-

from TR+ to TR-, the lens goes
toward the outer circumference.

Gain switching DVD one Layer

High gain

Sga

DVD two Layer

Sga : +5V

         CD

The signal drives the tracking servo mechanism which projects the beam on the track by moving the objective lens (OL) to the outer
or inner circumference (at a right angle against the track) of the disk.

2-focus objective lens

Actuator assembly

Monitor Diode

Basic Structure of Laser Diode

Laser Diode

LD

PD

The signal drives the focus servo mechanism which aligns the focus on the pit of the disk
by elevating OL (vertically against the disk surface.)

The VR terminal is connected to GND.

Since the laser diode largely varies output of the laser light even if the flowing current is slightly varied, the projection
light is detected with the monitor diode to control the laser light to be equally output.
Since the current varies on the monitor diode according to the intensity of the received light of the laser diode, the drive current of
the laser diode is reduced if the current of the monitor diode increases. On the contrary, the drive current of the laser diode is increased
if the current of the monitor diode decreases.
As the projection light of the laser diode becomes stronger, the current of the monitor diode increases to increase the current which
flows into the monitor diode output (PD).  This is input to the pin 44 of IC303 and is compared with the reference voltage to control
the drive current of the laser diode.
The circuit is called ALPC (Automatic Laser Power Control).

Power supply to drive the laser diode

The high-frequency convolution imposes the high-frequency signal on the DC current to impose the high frequency on the drive
current of the laser. Thus, the interference of outgoing light and reflected light is prevented.

Signals recorded in the disk

When the quantity of laser light increases, the current shown in
figure increases and the PD terminal voltage rises.
IC303 is used to control. The LD terminal voltage lowers, and
the quantity of light reduces. (IC303 is actuated by voltage
input.)