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SAMSUNG Proprietary-Contents may change without notice
Flow Chart of Troubleshooting and Circuit Diagrams
10-
6
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10-1-3. Sim Part
Phone can't access
SIM card
Check the pin 1 of
SIM300
Voltage = 3V
NO
Check the circuit related to
UCD300
YES
Check the SIM
connector's
(SIM300)
card
resolder or change
SIM300
NO
YES
Check the circuit around SIM300
input circuitry
NO
Check the related circuit of
SIM300
YES
NO
Check the related circuit of
UCD300
Check the circuit around
UCD300 output
and voltage supply circuitry
YES
END
C302
C305
5
6 6
G
7
8
G
G
9
10
G
SIM300
1
1
2
2
3
3
4 4
5
C301
C304
C300
C303
VSIM
SIM_RST
SIM_CLK
SIM_IO