Service manual

49
DV-NC70U/C
DV-NC72U
FLOW CHART NO.6
Is the focus control signal outputted to the pin(115)
of IC3701?
Check the pin(118) of IC3701 DAC power source
periphery circuit. If it is normal, replace IC3701.
Check the line between the IC3704 and the focus
actuator. Check CN3301.
Check M 8V line.
Is 8V voltage applied to the pin(22) of IC3704?
Check the pin(21) of IC3704 and replace IC3704.
Is the focus control signal from the pin(115) of
IC3701 inputted into the pin(23) of IC3704?
Check the focus control signal line between
the IC3701 and IC3704.
Is the focus control drive voltage outputted from the
pins(1) and (28) of IC3704?
Is the focus control drive voltage applied to the
terminal of focus actuator?
Check the connection of optical pickup cable.
If it is normal, replace the traverse chassis unit.
No
No
No
No
Yes
Yes
Yes
No
Yes
Yes
The [No Disc] indication. (In case focus servo does
not function.)
FLOW CHART NO.7-1
Check the S 5V line.
Is the control signal outputted from IC3301?
Is 5V voltage applied to the emitter of Q3304?
Is approx. 2V applied to the pin(21) of the pickup
terminal? (See note.)
Check the connection of optical pickup cable.
If it is normal, replace the traverse chassis unit.
Check the line between the Q3301, Q3302 and
Q3304.
Check or replace IC3301.
No
No
No
Yes
Yes
Yes
The [No Disc] indication during DVD playback.
(When the laser beam does not light.)
Note: Since the laser diode is very susceptible to static
electricity, be careful of static electricity or electricity
leak from the measuring equipment when confirming
the voltage.

FLOW CHART NO.7-2
Check the S 5V line.
Is the control signal outputted from pin(4) of IC3301?
Is 5V voltage applied to the emitter of Q3303?
Is approx. 2V applied to the pin(3) of CN3301?
Check the connection of optical pickup cable.
If it is normal, replace the traverse chassis unit.
Check the line between the Q3301~Q3303.
Check or replace IC3301.
No
No
No
Yes
Yes
Yes
Yes
The [No Disc] indication during CD playback.
(When the laser beam does not light.)
Note: Since the laser diode is very susceptible to static
electricity, be careful of static electricity or electricity
leak from the measuring equipment when confirming
the voltage.

FLOW CHART NO.8
Check the loading switch.
Check for contamination of objective lens of
optical pickup.
Replace traverse chassis unit.
Do you have loading done the disk by normality?
See FLOW CHART NO.9 and NO.10.
Set the disc on the disc tray.
Replace the Main PWB unit.
Is the level of RF signal which is outputted from
pin(31) of IC3301 normal?
No
No
No
Yes
Yes
Yes
Yes
Both picture and sound do not operate normally.(1)
FLOW CHART NO.9
Check the PC 5V line.
Set the disc on the disc tray.
Are the video signals outputted to the pins of main
unit connector CN3202?
CN3202 1pin S-Y
CN3202 3pin CB
CN3202 5pin S-C
CN3202 7pin CR
Check the main unit.
(IC3601, Q3201~Q3204 periphery circuit.)
Check between CN3202 and CN202.
No
No
No
No
No
Yes
Yes
Yes
Check the V-MUTE line.
Yes
Yes
Picture do not operate normally.
Are the video signals shown above inputted into
the pins of IC2001?
IC2001 2pin S-C
IC2001 6pin S-Y
IC2001 14pin CB
IC2001 16pin CR
Are the video signals outputted to each pins of
IC2001?
IC2001 33pin S-C
IC2001 31pin COMP
IC2001 28pin S-Y
IC2001 22pin CB
IC2001 19pin CR
Is 5V applied to the pins(1) and (13) of IC2001?
Replace IC2001.
Are the V-MUTE lines at the pins(3) and (15) of
IC2001 on "H" level?
*1
*2