Acer A221HQV Acer A221HQV LCD Monitor Service Guide - Page 33

5. Troubleshooting (continued) 5.1.8 Checking the resolution change IC movement: Check +3.3V supply on I304 pin2. ACER A211H/A221HQ 31 Go to contents page OK NG Proceed " Checking the DC/DC converter circuit" section. Check +1.2V supply on I305 pin 2. OK NG Proceed " Checking the DC/DC converter circuit" section. Check X301 27MHz clock input to I308 pin 127 and 128 at TTL level. OK NG Check I308 pin 125 RSTB signal is high level at normal operation. OK NG Check I308 pin 115,116,117 SPI signal. OK NG Failure Point I308 failure. Failure Point 1) Printed wire broke between X301 and I308 pin 127, 128. 2) C351, C352 is short or open. 3) X301 failure. Failure Point 1) Printer wire broke between I308 pin 125 and 2) C391 is short. 3) I308 is failure. Failure Point 1) Printed wire broke between I308 pin 115, 116, 117 and I309 pin 2, 5,6. 2) I309 is failure.