Key Sense Trouble - LG U8500 Service Manual

4. TROUBLE SHOOTING

4.11 Key Sense Trouble

Key Sense sequence of U8500 is :
Default condition ROW(0-4) is 2.7V -> Press the key -> Corresponding row(x) and col(x) go to 0V ->
Key sensing
RA600
R603
Side Key
For Volume
Start
Change the side key
pcb
Work well?
NO
Check the RA600,
R603 with no key press
ROW(0-4) is 2.7V?
YES
Check the RA600,
R603 with key press
NO
Change the Main board
- 102 -
Yes
End
NO
Check RA600,R603
Side Key
For Camera