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– 53 –

FRONT CBA

Ref No.

Position

Ref No.

IC2001

A-2

Q2002

IC2002

B-1

Q2003
Q2004

Q2001

A-1

Q2005

ICS

TRANSISTORS

TRANSI

FRONT PWB (BOTTOM VIEW)

– 54 –

Input
   CD: 1 kHz PLAY
           (WF4~WF6)
   DVD: POWER ON (STOP) MODE
           (WF1~WF3)

SPDIF

Q1351 Base

1V

0.2usec

Pin 6 of IC1402

Pin 2 of IC1402

AUDIO-L

Pin 7 of IC801

1V

0.5msec

AUDIO-R

Pin 8 of IC801

1V

0.5msec

Pin 4 of IC1402

VIDEO-Y

0.2V

20usec

VIDEO-CVBS 0.5V

20usec

VIDEO-C

0.2V

20usec

– 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