5. Troubleshooting (continued)
5.3.9 Checking the DC/DC converter circuit:
OK
NG
Failure Point
1) Power wire disconnection.
2) Power board is failure.
OK
NG
Failure Point
Printed wire broke between CN301
pin 9, 10, 11 and I301 pin3.
Failure Point
I301 is failure or C303 is short.
OK
NG
OK
NG
Failure Point
D301 is failure or Q302 is failure or
C307 is short.
Failure Point
Printed wire broke between D301 and
L310.
Printed wire broke between I301 pin2 and
L308 L309.
L308 L309 L310 open or C304 C338 C387
C380 C332 C333 C334 C330 C331 short.
Check the 5V is output from
CN301 pin 9,10,11
Check the 5V is input to I301 pin3
Check the 3.3V is output
from I301 pin2
Check the 1.2V is input to D301
55
ACER A211H/A221HQ