Acer A221HQV Acer A221HQV LCD Monitor Service Guide - Page 53

5. Troubleshooting (continued) 5.3.5 Abnormal OSD display adjust problem: ACER A211H/A221HQ 51 Go to contents page Check the input level whether was changed when pressed function keys on the CN305 pin 1, 2. (Normal is 3.3V, when push button, generted different voltage. Pin 1, 2 is 0.69V or 1.65V or 2.11V) Failure Point NG 1) Function key wire disconnection. 2) Function key wire is failure. 3) Function key board is failure. OK Check the input level whether was changed when pressed function keys on the I306 pin 58, 539. (Normal is 3.3V, when push button, genertaed 0.69V or 1.65V or 2.11V) Failure Point 1) Printed wire broke between CN305 pin 2, 1306 pin 58. NG 2) Printed wire broke between CN305 pin 1, 1306 pin 59. 3) C366 or C367 is short. 4) R370 or R371 is short or open. 4) R372 or R373 is open. OK Failure Point I306 is failure