Acer X223 X223W LCD Service Guide - Page 23

22 ACER X223W Go to cover page 5. Troubleshooting (continued) 5.2 Nothing display on screen (screen is black, color of LED is blue) continued Continue Check the 5V power supply for P304 pin 1, 2, 3 NG Check the I302 pin2 NG if voltage is 3.3V Proceed "Checking the DC/DC converter circuit" section. OK Check the D326 pin1 if voltage is 1.8V NG Proceed "Checking the DC/DC converter circuit" section. OK OK Failure Point Check the I301 pin2 if voltage is 5V NG 1) FB301 is open. 2) C309, C310 is short. OK Check if the voltage between I301 pin2 and pin3 is above - 0.7V NG OK Check the input voltage level whether was changed when pressed function keys on the P306 pin 4 (normal is high level, when push buttom, generated 1.6V) Failure Point I301 is failure. NG Check if the Q301 pin2 of PANELVCC_EN signal that outputted by I305 pin85 is High level. OK Failure Point NG Failure Point 1) Printer wire between R307 and I305 pin85 is failure 2) I305 is failure. 1) Printed wire between Q301 pin3, R305, R306, I301 pin1 is failure.. 2) Q301 is failure. OK Check the P304 all LVDS signals. NG OK Failure Point 1) The LVDS cable broke between P304 and LCD module. 2) LCD module is failure. Check if the voltage on I305 pin 90 that is from 3.3V to 1.6V. NG OK Failure Point I305 is failure Failure Point 1) Printed wire broke between P304 and I305 LVDS signals. 2) I305 is failure. Failure Point Printed wire broke between P306 pin 4 and I305 pin 90.