Keypad Backlight Trouble - LG KU950 Service Manual

4. TROUBLE SHOOTING

4.14 Keypad backlight trouble

Key Pad Back Light is on as below :
Key pressing → KYPD_LED_EN go to Low → LED On
Key Pad LED controlled by PM6650.
Change the Main or
KEY Board.
Start
Key press
Signal VPWR is OK?
Yes
NO
Signal KYPD_LED_EN
is OK?
Yes
Check the serial resister
For each LED
Work well?
NO
Yes
End
LD100~103_KEY,
VPWR(
KYPD_LED_EN(VA908,VA101)
- 116 -
NO
Check LD900~910 (Main)
and R100~103 (Key)
LD900~910_Main)