Keypad Backlight Trouble - LG LG9200 Service Manual

4. TROUBLE SHOOTING
4.1.7 Keypad Backlight Trouble (Qwerty Key) : (1)
• Block Diagram
VBAT
Calypso
U102
C601
• Backlight Operation
- The keypad EL backlight is controlled with
KEY2 signal.
- KEY2 signal from DBB.
L601
Tr.
Q602
EL charge pump
KEY2
U602
C602
- 60 -
EL backlight key pad
• Check Point
- KEY2 signal
- Soldering state of components
- EL key pad