Acer X193 X183H / X193HQ Service Guide - Page 29

28 ACER X193HQ Go to cover page 5. Troubleshooting (continued) 5.9 Checking the interface circuit of sync signal 5.9.1 Checking 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 Failure Point Video cable is failure. Check the horizontal sync signal on I308 pin8 TTL level. 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.