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ACER X193HQ
5. Troubleshooting (continued)
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5.9Checking the interface circuit of sync signal
5.9.1Checking the control circuit of horizontal sync pluse
Check the horizontal sync signal on P302 pin13 TTL
level.
NG
OK
Failure Point
Video cable is failure.
Check the horizontal sync signal on I308 pin9 TTL
level.
NG
OK
Failure Point
Process "Checking the resolution change IC movement" section.
Failure Point
1)Printed wire broke between P302 pin13 and I308 pin9.
2)FB304 , R309 is open.
3)D307 ,R319 or C322 is short.
5.9.2 Checking the control circuit of vertical sync pluse
Check the vertical sync signal on P302 pin14 TTL level.
NG
OK
Check the horizontal sync signal on I308 pin8 TTL
level.
Failure Point
Video cable is failure.
NG
OK
Failure Point
Process "Checking the resolution change IC movement" section.
Failure Point
1)Printed wire broke between P302 pin14 and I308 pin8.
2)FB305 or R308 is open.
3)D310,R318 or C313 is short.