Toshiba DVR80KF Service Manual page 34

3 VCR Section
FLOW CHART NO.1
The key operation is not functioning.
Are the contact point and the installation state of the
key switches normal?
Is the control voltage normally inputted into Pin(7) of
IC501?
Replace P1(AV ASSEMBLY).
FLOW CHART NO.2
No VCR operation is possible from the remote control. (Operation is possible from the unit.)
Is 5V voltage supplied to the Pin(3) terminal of the
RS1501 (remote control receiver)?
Is the "L" pulse sent out from Pin(1) terminal of the
RS1501 (remote control receiver) when the remote
control is activated?
Is the "L" pulse signal supplied to Pin(14) of IC501?
Replace P1(AV ASSEMBLY).
Yes
Yes
Yes
Yes
Yes
No
Re-install some key switches correctly or replace
P1(AV ASSEMBLY).
No
Check the key switches and their periphery, and replace
P1(AV ASSEMBLY) if defective.
Terminal voltage of IC501-7
4.30
3.60
2.90
2.39
1.98
1.61
1.27
0.92
0.51
(V)
No
Check SYS+5V line and replace P1(AV ASSEMBLY)
if defective.
No
Replace the RS1501 (remote control receiver).
Replace P1(AV ASSEMBLY) or remote control (X1).
No
Check the line between the RS1501 (remote control
receiver) and Pin(14) of IC501, and replace P1(AV
ASSEMBLY) if defective.
1-11-11
KEY-1
IC501-7
S-INH
CH-UP
CH
-DOWN
REC
PLAY
FF
REW
STOP
/EJECT
POWER
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