User Guide

5-7 Flow chart of trouble shooting and Circuit Diagram
5-4 Sim Part
U101 pin6 = 3 V ? Resolder R103
END
Yes
No
Yes
Check the circuit around U107
(Serial EEPROM) and data stored in it
Yes
Phone can't access SIM card
Yes
U101 pin 5 = "H" ?
U101 pin 2, 3 = 3 V ?
Replace the PBA
Replace U101
Yes
No
No
CN102 pin 1, 5 = 3 V ?
Resoldering CN102
and check open connection
from U101 to CN102
No
After Power ON,
Check SIMCLK Signal on CN102 pin 3
in a few second
After SIM card insert,
CN102 pin 2 = "H(SIMRST) ?
Replace PBA
Replace the PBA
Yes
Yes
No
No
R699 = 2.9 V ?
Yes
No
Check the circuit related to U463
U463 pin1 = 3 V ?
Yes
No
Check the circuit related to
R421, R428, U649