Acer B277 - Page 17

17
5.4 LED backlight debug flow：
LED driver Debug
Check Net
19V_BLD is
19V?
Replace FB36
FB36 is
open?
BD4 is damaged?
BU3 is damaged?
Replace BU3
Check U12 works
END
N
Y
Y
N
Y
N
Replace BD4
Backlight on?
Y
N
BR31 is open?
Replace BR31
Y
N
Open BR67
Y
N
Check BU5 pin5
is high ?
Check NET BL_CTRL
level is high?
Reassemble BR67
Y
N
Y
Y
N
Replace BU5