LG CU920 - Camera Module Troubleshooting Steps

4.15 Keypad Backlight Troubleshooting
Key Pad Back Light is on as below :
Key pressing → LED_CON go down low (below 0.8v) → MAIN Key Backlight LED On
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4. TROUBLE SHOOTING
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Start
Chang e the Main bo ard
Check ba ttery
NO
Yes
Yes
Key press
Chang e the Main bo ard
Yes
NO
+VPWR is ab ov e 3.2V?
LED_CON is low?
R102 & R103 is
conne cted ground
?
Yes
Chang e the KEY FPCB
NO
LED_CON
Figure. Side key FPCB backlight LED part
KEY LED