HP WF1907 Service Manual page 24

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Check I310 pin 14 SHOUTDOWNn if is low
level.
OK
Check I310 pin 10, 12, 20, 2 audio signal output.
OK
Check audio speaker is working.
OK
Failure Point
Audio speaker unit "L" or "R" is failure.
Failure Point
NG
1) Printed wire broke between I306 pin 51 and Q309
and I310 pin 14.
2) R392, R390, R391 is open or short.
3) C400 is short.
4) Q309 is filure.
5) I306 is failure.
Failure Point
NG
1) Printed wire broke between I310 pin10, 12, 20, 2 and
P310 pin 1, 2, 3, 4.
2) I316 is failure.
Failure Point
NG
1) Audio output wire is disconnected from the interface
board P310 to key function board P601.
2) Printed wire broke between P600 and P601 and P602
for the key function board.
3) Audio speaker unit is disconnected from the P601
and P602.
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