Sharp BD-HP75U

BD-HP75U
4 – 6
Flowchart 10
RS232C does not work normally.
Does it work normally after replacing the cable? YES The cable is defective.
NO
Are there signals on SC4701: 2, 3pin? YES Check if SC4701 is in poor contact, or replace it.
NO
Are there signals on IC4701: 8, 13pin? YES Check R4705, 4706, FB4701, and 4702.
NO
Are there signals on IC4701: 9, 11pin? NO Check P4701 and harness. Does it work normally after replacing
them?
YES
NO
Check the peripheral circuits of IC2501.
Is there 3.3V on IC4701: 15, 16pin? NO Check the power circuit.
YES
Check or replace the peripheral circuits of IC4701.