Acer A221HQV - Check the Backlight Unit

5. Troubleshooting (continued)
5.3.3 Check the backlight unit:
OK
NG
Failure Point
1) The wire between Power +22V and
Inverter +22V is broken.
2) Power board failure.
OK
NG
Failure Point
1) Printed wire broke between CN301
pin 13, and I306 pin 56.
2) R301 is open.
3) I306 is failure.
Failure Point
Back light unit of LCD module is failure.
Is +22V supplied to inverter PWB?
(by the power board)
Check the BACKLIGHT_ADJ
signal of the CN301 pin 13 from I306
pin 56 is a PWM signal.
49
Go to contents page
ACER A211H/A221HQ