Acer AL2002 Service Manual page 48

ACER AL2002W
12
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Checking the resolution change IC movement
1. Check +3V3 supplied on I306
pin2, pin25, pin53, pin47, pin74, pin82, pin91,
pin92, pin101. pin110, pin116
2. Check +3V3 supplied on I309 pin8.
OK
1. Check +1V8 supplied on
I306 pin55, pin87, pin17,
pin118, pin70, pin78, pin104, pin106.
2. Check +1V8 supply on I305 pin46, pin53,
pin86, and pin122.
OK
Check X301 14.318MHz clock input to I306
pin108 and pin109 at TTL level
OK
Check I306 pin111 RSTB signal is high level at
normal operation.
OK
1.Check I309 pin8, pin3, pin5, pin6.
2.Check I308 pin5, pin6, pin7, pin8.
OK
Failure Point:
I306 is defected.
Appendix 4: Troubleshooting
NG Proceed 'Checking the DC/DC converter circuit' section
NG Proceed 'Checking the DC/DC converter circuit' section
Failure Point:
1. Printed wire broke between X301 and I306 pin108
NG and pin109
2. C362 or C373 may be short or open.
3. X301 is damaged.
Failure Point:
1. Printed wire broke between I306 pin111 and I307
pin2.
NG
2. C375 is short.
3. I307 or I306, Q305 is damaged.
4. R349, R348 is open.
Failure Point:
1. Printed wire broke between I309 pin5, pin6 and
I306 pin61, pin62.
NG
2. I306, I309 is defected.
3. R362,R364,R365,R366,R359,R360 or R361
is open.