Denon MC2000 Service Manual page 35

FLOW CHART NO.8 (405-MC2-3058 : CONTROL UNIT)
The key operation is not functioning.
Are the contact point and the installation state of the key
switches (SW400 - SW448) and rotary encoder (SW449 -
SW451) nomal?
Does LED (D460 - D498) light correctly?
When pressing each key switches, turning rotary switches and turning rotary
encoder, does the voltage of each pin of IC400 (shown below) decrease?
Key switches
SW400, SW406, SW412, SW418, SW424, SW430
SW401, SW407, SW413, SW419, SW425, SW431
SW402, SW408, SW414, SW420, SW426, SW432
SW403, SW409, SW410, SW421, SW427, SW433
SW404, SW410, SW411, SW422, SW428, SW434
SW405, SW411, SW412, SW423, SW429, SW435
SW437, SW438, SW441, SW444, SW446, SW448
SW436, SW439, SW440, SW442, SW445, SW447
SW443
Rotary encoder
SW449, SW450, SW451
Replace IC400.
YES
YES
: IC400 55pin
: IC400 56pin
: IC400 57pin
: IC400 58pin
: IC400 59pin
: IC400 66pin
: IC400 67pin
: IC400 70pin
: IC400 71pin
: IC400 71pin
YES
NO
Re-install the switches correctly or replace the poor switch.
NO
Check the Q400 - Q405, Q410 - Q417 and their periphery,
and replace it if defective.
Check key switches (SW400 - SW448), rotary
NO
encoder (SW449 - SW451) and their periphery,
and replace it if defective.
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