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SELF-DIAGNOSIS
This model has the self-diagnosis function for the VIDEO and AUDIO decoder sections.
Immediately after the power on, the self-diagnosis function searches each operation of IC’s around the mechanism control microcomputer
(IC701).
The results can be checked by D502 of the VIDEO board.
• When D502 turns on the IC is normal.
• When D502 flashes twice, the MPEG decoder (IC505) is abnormal.
• When D502 flashes three times, the MPEG decoder (IC505) or
the DRAM (IC507) is abnormal.
[VIDEO BOARD] (SIDE A)
D502
IC505
100
91
33
64
90
65
1
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