Service manual

Page 18
AL1702
Confirm the host computersupplies DDC2 mode.
OK
NG
Failure Point
The host machine is not communicatiog in DDC2
mode.
Check the voltage on I304 pin8 that is power DC 5
V.
OK
NG
Failure Point
1) Printed wire broke between I304 pin8, D309,
D310 and P302 pin13.
2) D309 or D310 is failure.
3) D315 is failure.
Check the output signal of serial data / clock on I304
pin5, 6.
OK
NG
Failure Point
I304 is failure.
Check the voltage on P302 pin13 that is power DC
5 V.
OK
NG
Failure Point
TheVideo cable is failure.
Check the voltage on P302 pin11, 12 that is serial
data / clock signal.
OK
NG
Failure Point
TheVideo cable is failure.
Failure Point
1) Printed wire broke between I309 pin2, 3, I304
pin5, 6 and P302 pin11, 12.
2) I309 maybe failure.
3) R336, R337 is open.
4) C349, C350 is short.
6. Abnormal plug and play operation