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SAMSUNG Proprietary-Contents may change without notice
Flow Chart of Troubleshooting
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7-19
10. Key Back Light
1. Main Key Part
2. Sub Key Part
U502 PIN46 = "H"?
Check the U502 or Replace PBA
END
No
Yes
Yes
Sub Key Backlight does not work
U600 pin 4 = "H"?
No
Check the U600
Yes
C430 = "H"?
Check the PMU related to "VDD_KEY"
END
No
Yes
Yes
Main Key Backlight does not work
CN601 PIN6 = "H"?
Change the board to board
FPCB
No
Yes