Sim Part - Samsung SGH-T508 Service Manual

5-4 Sim Part

Phone can't access SIM card
Check SIMCLK Signal on CN100 pin 3
After SIM card insert,
CN100 pin 2 = "H(SIMRST) ?
Check the circuit around U402
(Serial EEPROM) and data stored in it
5-7
Yes
U101 pin4 = 3.0 V ?
Yes
U101 pin5 = "H" ?
Yes
U101 pin 2, 3 = 3.0 V ?
Yes
After Power ON,
in a few second
Yes
Yes
END
No
Check the circuit around U104
No
Replace U101 or
Replace PBA
No
Replace U101
No
Resoldering C109 or
Replace PBA
No
Replace PBA
Flow Chart of Troubleshooting and Circuit Diagrams