50
DV-NC70/W
DV-NC70X/RU
(D
VD)
FLOW CHART NO.1
Is the supply voltage of 5V fed up to pin(37) of
IC8051?
Check the AT 5V line.
Is the supply voltage of 3.4V, 1.7V fed up to pin
(38), (39) of IC8051?
Check the pins(38) and (39) of IC8051 and their
periphery circuit.
Check the signal lines of LCD RESET, LCD CS,
LCD CLK, LCD DATA on pins(36), (42), (43), (44)
of IC8051.
Check signal line of LCD RESET, LCD CS, LCD
CLK, LCD DATA on pins(6), (12), (8) (10) of IC801.
Is the OSC signal present on pin(41) of IC8051?
Check periphery circuit of pin(41) of IC8051.
Are common and segment signals supplied from
IC8051 (LCD driver IC) to LCD8052 (LCD)?
Replace IC8051.
Check that the LCD display tube is free from
damages.
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Check signal line between IC3501 and IC801.
Check signal of LCD RESET, LCD CS, LCD CLK,
LCD DATA on pins(5), (13), (9), (11) of IC801.
Yes
Check the signal lines between IC801 and IC8051.
Check or replace IC801.
The LCD display tube does not turn on.
No
No
FLOW CHART NO.2
Is key switch contact and installation state normal?
Replace key switch.
Is the control voltage into the pins(72), (73) of
IC3501 normal?
No
Yes
The key operation is disabled.
KEY-1/2
3.3V
2.5V
1.8V
0.9V
0V
KEY
–
2
KEY
–
1
OFF
SW8053
STOP
SW8052
PLAY
Check AT 5V line.
Replace the remote control receiver.
FLOW CHART NO.3
Operation is possible from the DVD, but no
operation is possible from the infrared remote
control.
Replace the remote control receiver or replace the
remote control transmitter if necessary.
Is 5V voltage supplied to the pin(3) terminal of
remote control receiver?
Check the line between the remote control receiver
and the pin(42) of IC3501.
Is the "L" pulse sent out from pin(1) terminal of receiver
when the infrared remote control is activated?
Is pulse signal supplied to the pin(42) of IC3501?
Replace IC3501.
No
No
No
No
Yes
Yes
Yes
Yes
No operation is possible from the infrared remote control.
FLOW CHART NO.4
Is the LOAD signal inputted to the pin (4) of IC3704?
Check pin(61) of IC3701. Check LOAD signal line
between IC3701 and IC3704.
Check IC3704.
Check for mechanism and gear engagement and breakage.
Is loading motor drive voltage outputted from the
pins(11) and (12) of IC3704?
Is the loading motor drive voltage applied to the
terminal of loading motor?
Check the line between the IC3704 and the
loading motor. Check CN3702.
No
No
No
Replace IC3704.
Yes
Yes
Yes
Yes
The disc tr
a
y
cannot be opened and closed.
No
Is FE signal inputted into the pin(117) of IC3701?
Check or replace IC3701.
Check the line between the IC3301 and IC3701.
FLOW CHART NO.5
Does the optical pickup move up and down after
the disc is removed? (Checking of symptom.)
See FLOW CHART NO.6. <The [No Disc] indication.
(In case focus servo does not function.)>
Replace IC3301.
Is there input signal on the pins(49), (50), (51), (52)
of IC3301?
Is FE signal outputted from the pin(22) of IC3301
when the disc is set?
Check the connection of optical pickup cable.
If it is normal, replace the optical pickup.
No
No
Yes
No
Yes
Yes
Yes
The [No Disc] indication.
(In case of f
ocus error)