User Guide

5-17 Flow chart of trouble shooting and Circuit Diagram
5-10 Back Light
Yes
END
Backlight does not work
Select backlight "ON" mode
Backlight "ON" mode
in the menu?
R141 = "H" ? GPO1 by test S/W
No
Yes
Yes
No
Check the
CN105 pin 17
Check the CN105 pin 17 = "H" ?
LCD backlight on ? Replace EL sheet
No
Yes
No
LCD BACKLIGHT
KEY PCB LED
Resolder R141, R149 Q107 pin 1 = "H" ?
No
Yes
Resolder Q107 Q107 pin 3 = "L" ?
No
Yes
Yes
END
Key PCB LED on ?
Resolder CN503
or Replace Key PCB
No