Acer AL2002 AL2002 Service Guide - Page 48

12 ACER AL2002W Go to cover page Appendix 4: Troubleshooting 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. NG Proceed 'Checking the DC/DC converter circuit' section 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. 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 NG pin2. 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 NG I306 pin61, pin62. 2. I306, I309 is defected. 3. R362,R364,R365,R366,R359,R360 or R361 is open. OK Failure Point: I306 is defected.