Tali Budur wrote:
May I kindly request your help to solve the problem?
How could anyone help you when you haven't provided any information
about what actually fails?
"can't detect sim card" is not a useful error report, it merely
describes a symptom. From that it is impossible to say what your
problem is.
Use an oscilloscope or logic analyzer to investigate various points
on the PCB.
Use debugging statements inside the firmware to investigate what is
going on in the firmware.
Provide the mailing list with detailed information about what
actually goes wrong. You have to do that investigation yourself.
Only then can you actually get some help.
//Peter