Service manual

4.7 Abnormal plug and play for VGA
Confirm the host computer supplies DDC2
mode.
Fa ilu r e Poin t:
The host computer is not communicating in DDC2 mode.
Check the voltage on P302 pin10
that is power DC 5V.
NG
OK
Failure Point:
The VG A video cable is defected.
NG
OK
Check the voltage on I304 pin8
that is power DC 5V.
NG
Fa ilu r e Poin t:
1. Printed wire is broken between P302 pin9 and I304 pin8
2. D307 or D308 is dam aged.
Check the voltage on
P302 pin12, pin15 that are serial
data and clock signal.
OK
Fa ilu r e Poin t:
The VG A video cable is damaged. If I304 pin5, pin6 LOW,
the I304 may be failure.
NG
Fa ilu r e Poin t:
1. R328, R329, R326, R327 is open.
2. D309, D310 is short.
3. C331, C332 is short.
Check the output signal of serial data and
clock signal I304 pin5 and pin6
Fa ilu r e Poin t:
I304 is defected.
NG
OK
OK
4. Troubleshooting (continued)
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ACER AL1716W