Flow Chart No.6; Flow Chart No.7; Flow Chart No.8 - Denon DCD-720AE Service Manual

FLOW CHART NO.6

No operation is possible from the remote control unit.
Is MCU+3.3V_2 voltage supplied to Pin(3) terminal of the infrared
remote control receiver (IC75)?
YES
Is the "L" pulse sent out Pin(1) terminal of receiver (IC75) when the
infrared remote control is activated?
YES
Is the "L" pulse supplied to the Pin(6) of IC11?
YES
Replace IC11

FLOW CHART NO.7

The disc tray cannot be opened and closed. (It can be done using the remote control unit.)
Is the normal control voltage inputted to Pin(92) of IC11? Refer to
"FLOW CHART NO.6" <The key operation is not functioning.>
YES
Refer to "FLOW CHART NO.9" <The disc tray cannot be opened and
closed.>

FLOW CHART NO.8

The disc tray cannot be opened and closed.
Check the line between CWC7 and IC31, and service it if defective.
NO
Check MCU+3.3V_2 line and service it if defective.
NO
Replace the infrared remote control receiver (IC75) or
replace the remote control unit.
NO
Check the line between Pin(1) terminal of receiver(IC75)
and Pin(6) of IC11, and service it if defective.
NO
Replace the "OP/CL" button (S706).
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