HP WF1907 Service Manual page 20

4.6.2 Abnormal plug and play operation for DVI
Confirm the host computer supplies DDC/CI mode.
OK
Check the voltage on P303 pin 14 that is DC 5 V.
OK
Check the voltage on I305 pin 8 that is DC 5 V.
OK
Check the signals if is high on P301 pin 7, 6 that is I2C
data / clk signal.
OK
Check the output signal of I2C data / clk on I305 pin 5,
6.
OK
Failure Point
1) Printed wire broke between I306 pin 67, 66, I305 pin
5, 6 and P303 pin 7, 6.
2) I306 maybe failure.
3) R346, R347 is open.
4) C346, C347, R324, R343 is short.
NG
Failure Point
The host machine is not communicated in DDC/CI
mode.
NG
Failure Point
The DVI-D video cable is failure.
Failure Point
NG
1) Printed wire broke between I305 pin 8, D320 and
P303 pin 14.
2) D320 is failure.
NG
Failure Point
The DVI-D video cable is failure.
NG
Failure Point
I305 is failure.
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