Samsung DSR9500 VIA CI Service Manual page 37

Troubleshooting
NO S/W DOWNLOAD
4-6
R258, R259 voltage
is 8~10V?
Yes
U200 (11, 12, 13, 14)
occur data waveform
Yes
Check U108.
Yes
Check U100.
No
Check DB201, RS232 cable.
No
Check U201.
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