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SAMSUNG Proprietary-Contents may change without notice
Flow Chart of Troubleshooting
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9-9
2)Slave
SIM900 pin 1,5 = "H"?
Phone can't access SIM Card (slot2)
Resolder or replace UPL900
Check the SIM Card
END
No
Yes
Yes
Yes
No
Check the Clock
After Power ON,
Check SIM_CLK_2 Signal on
pin3 of SIM900 in a few second
Yes
No
Replace PBA
After SIM card insert,
SIM900 pin 2 = "H(SIM_RST_2)"?
Yes