Abnormal Plug And Play Operation - HP f1723 Service Manual

f1723 / FP7317 / L1702 / vf17 / FP17

6. Abnormal plug and play operation

Confirm the output of serial data on I303 pin 6 synchronize SCLK at TTL level.
Failure point
NG
I304 failure.
OK
Failure point
1) The host machine isn't communicating in DDC2 mode.
2) The video cable may have failed or may not to have connections for DDC.
3) Between I303 pin 6 and P302 pin 12 may have failed.
4) R310, R385 open.
5) Cable failure.
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