White screen
3、Display Trouble (white screen)
Check if the voltage of panel power
supply is normal(depend on panel)
NY
Is there voltage on grid of
Q8/WPM3407 can changed
(12~0V or 5V~0)
Is there output signal
from U12
NY
Y
N
CN4 is ill-connected
(is there voltage for panel)
or Q8 is damaged
Check if the circuit of Q9 normal?
Change the LCD panel
or the cable to panel
U12 is illness
Check if the I/O of U12 is damaged
(the 132th pin)
Q9 is damaged