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– 55 –

The power cannot be turned on. 

The fuse blows out.

After servicing, replace the fuse.

Is the fuse normal ?

Is normal state restored when once unplugged 
power cord is plugged again after several seconds ?

Is the EV 5V line voltage normal ?

Is each voltage of the secondary side normal ?

Check the presence that the primary component
is leaking or short then service it if defective. 

See FLOW CHART No. 2  <The fuse blows out.>

Check if there is any leak or shor-circuiting on the 
primary circuit component.
(Q1001, Q1003, T1001, D1001, D1002, D1004, 
D1005, D1011, C1003, C1005)

Check each rectifying circuit of the secondary circuit.

Check the presence that the rectifying diode or
circuit is shorted in each rectifying circuit of 
secondary side then service it if defective. 

Yes

Yes

Yes

No

No

No

No

When the output voltage fluctuates

Yes

No

No

FLOW CHART NO.4
When buzz sound can be heard in the vicinity of power circuit.

Check if there is any short-circuit on the rectifying diode and the circuit in each rectifying circuit of the secondary side.
( D1008, D1009, D1013, D1030, IC1002, Q1002, Q1004, Q1007, Q1011, Q1014)

Does the photo coupler circuit on the secondary 
side operate normally ?

Does the photo coupler circuit on the primary side
operate normally ?

Check the circuit and replace the parts.
(IC1001, IC1006, D1048, D1015)

Check the circuit and replace the parts.
(IC1001, D1012, D1024)

– 56 –

Yes

Yes

Yes

Yes

No

No

No

No

LCD (FL2001) is not functioned.

Is the voltage of 5V supplied to Pin(56) of IC2001 ?

Is there 38 kHz oscillation at Pin (60) of IC2001 ?

Check the signal lines of FP-DIN, FP-DOUT, 
FP-CLK, FP-STB of IC2001 and CN1001 ?

Replace the LCD (FL2001).

Check the EV 5 V line.

Check R2001, C2004, IC2001 and their periphery.

Check or replace IC2001 and DVD Main CBA unit.

The key operation is disabled.

Is key switch contact (SW2001-2003, 2005-2007) 
and installation state normal ?

Is the control voltage normally inputted into  
Pins (44-47, 50, 51) of IC2001 ?

Check the key switches (SW2001-2003, 
2005-2007), and their periphery circuit.

No operation is possible from the remote control unit.

Operation is possible from the DVD, but no
operation is possible from the remote control unit.

Is no operation possible if replacing the remote 
control unit ?

Replace the infrared remote control receiver.

Original remote control unit is poor.

Check the line between the infrared remote control 
receiver and Pin (23) of CN1001.

Replace DVD Main CBA unit.

Is the "L" pulse sent out Pin (1) terminal of receiver
when the infrared remote control is activated ?

Is the "L" pulse signal supplied to the Pin(25) of 
CN1001 from Pin (1) of receiver ? (Be operated by 
SEARCH (-), SEARCH (+), PLAY, STILL/PAUSE, 
STOP, POWER and OPEN/CLOSE button.)

Yes

Yes

Yes

Is 5V voltage supplied to the Pin (3) terminal of
the infrared remote control receiver (RM2001) ?

Yes

Yes

No

P-ON 12 V is not outputted.

Is P-ON12 V voltage supplied to the collector of Q1002 ?

Does the P-ON switch circuit operate normally ?
(Q1005, Q1006, D1036, etc.)

Replace Q1002.

Check D1009, C1012 and the periphery circuit.

Check each component and if poor, then replace.

Yes

Yes

No

No

No

Check EV 5 V line.

No

No

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P-ON 1.8 V is not outputted. 

The disc tray cannot be opened and closed. 
(It can be done using the remote control unit.)

The disc tray cannot be opened and closed.

Is 2.5 V voltage supplied to Pin (1) of IC1002 ?

Is 5 V pulse supplied to Pin (46) of IC2001 when 
the OPEN/CLOSE button is activated on the DVD ?

See FLOW CHART NO. 13. <The disc tray cannot be opened and closed.>

Is the "H" pulse inputted into Pin (4) of IC1002 ?

Replace IC1002.

Replace the DVD Main CBA Unit.

No improvement can be found.

Replace the DVD Mecha.

Check D1013, C1014 and their periphery circuit.

Check PWRCON line.

Check the SW2003 and OPEN/CLOSE button.

The malfunction of the original DVD Main CBA Unit. 

Yes

Yes

No

Yes

No

No

No

Yes

P-ON 3.3 V is not outputted.

Is 3.3 V voltage supplied to the emitter of Q1011 ?

Does the P-CON switch circuit operate normally ?
(Q1005, Q1006, etc.)

Replace Q1011.

Check D1008, D1015, C1007, C1038 and their 
periphery circuit.

Check each component and if poor, then replace.

Yes

Yes

No

No

P-ON 5 V is not outputted. (PON 12 V is outputted normally.)

Is 5 V voltage supplied to the collector of Q1004 ?

Is the "H" pulse inputted into the base of Q1004 ?

Replace Q1004.

Check D1030, D1048, C1035, C1048 and their 
periphery circuit.

Check Q1004, D1046 and the periphery circuit.

Yes

Yes

No

No

– 58 –

[No Disc] indicated. (When the focus servo is not functioning.)

FLOW CHART NO.16
[No Disc] indicated. (When the laser beam does not light up.)

FLOW CHART NO.17
Both functions of picture and sound do not operate normally. 

Replace the DVD Main CBA Unit.

Replace the DVD Mecha.

No

Yes

Replace the DVD Main CBA Unit.

Replace the DVD Mecha.

No

Yes

Replace the DVD Main CBA Unit.

Replace the DVD Mecha.

No

Yes

No improvement can be found.

The malfunction of the original DVD Main CBA Unit. 

No improvement can be found.

The malfunction of the original DVD Main CBA Unit. 

No improvement can be found.

The malfunction of the original DVD Main CBA Unit. 

[No Disc] indicated. (When the focus error occurs.)

Replace the DVD Main CBA Unit.

No improvement can be found.

The malfunction of the original DVD Main CBA Unit. 

Replace the DVD Mecha.

No

Yes