Acer A221HQV Acer A221HQV LCD Monitor Service Guide - Page 46

44 ACER A211H/A221HQ Go to contents page 5. Troubleshooting (continued) 5.2.8 Checking the resolution change IC movement: Check +3.3V supply on I310 pin 49, 84, 106, 62, 1 Proceed " Checking the DC/DC converter NG circuit" section. OK Check +1.2V supply on I310 pin 60, 73, 120. 23 Proceed " Checking the DC/DC converter NG circuit" section. OK Check X301 14.318MHz clock input to I310 pin 127 and 128 OK Check I310 pin 125 RESET signal is high level at normal operation. OK Check I310 pin 115~118 SPI Flash ROM interface signal. OK Failure Point I310 failure. Failure Point 1) Printed wire broke between X301 and I310 NG pin 127, 128. 2) C360, C361 is short or open. 3) X301 is failure. Failure Point 1) Check I310 pin125 is from high to low level, it is 3~10ms high level, when VCC5V is turned on. NG 2) Printed wire broke between I310 pin 125 and C362/R376. 3) R376 is short or open.. 4) I310 failure. Failure Point NG 1) Printed wire broke between I310 pin 115~118 and I307. 2) I311 failure.