Sharp DV-NC200SS Service Manual page 36

2. DVD Section
FLOW CHART NO.1
The key operation is not functioning.
Are the contact point and the installation state of
the key switches (SW2020, SW2021, SW2022) normal?
When pressing each key switches (SW2020,
SW2021, SW2022), do the voltage of each pin
of CN1051 (shown below) change to "H" (3.3V)
from "L" (0V)?
SW2020 → CN1051 24PIN
SW2021 → CN1051 26PIN
SW2022 → CN1051 25PIN
Replace DVD Main CBA.
FLOW CHART NO.2
No DVD operation is possible from the remote control unit. (Operation is possible from the unit.)
Is 5V voltage supplied to Pin(3) terminal of the
RM2001 (remote control receiver)?
Is the "L" pulse sent out from Pin(1) terminal of the
RM2001 (remote control receiver) when the remote
control unit is activated?
Is the "L" pulse signal supplied to Pin(22) of
CN1051?
Replace the DVD Main CBA.
FLOW CHART NO.3
The disc tray cannot be opened and closed. (It can be done using the remote control unit.)
Does the voltage of Pin(24) on CN1051 become
3.3V when pressing "OPEN/CLOSE" button on
the unit?
Refer to "FLOW CHAR NO.4" <The disc tray
cannot be opened and closed.>
Yes
Yes
Yes
Yes
Yes
Yes
No
Re-install the key switches (SW2020, SW2021,
SW2022) correctly or replace the poor switch.
No
Check the key switches (SW2020, SW2021,
SW2022) and their periphery, and service it if
defective.
No
Check AL+5V line, and service it if defective.
No
Replace the RM2001 (remote control receiver).
Replace remote control unit if needed.
No
Check the line between the RM2001 (remote
control receiver) and Pin(22) of CN1051, and
service it if defective.
No
Replace the "OPEN/CLOSE" button (SW2020).
1-11-4
H9941TS