No IMEI/No Modem Firmware/Unable to activate
The modem firmware number shown in “About” means that there is baseband, if no modem firmware shown in “about” it means there is no baseband, do not insert SIM card and then access dial-up interface to input * # 06 # directly, under normal circumstances, IMEI serial number will be shown same as what you can find in “about” interface.In this iPhone, no IMEI serial number shown when dial * # 06 #, since we’ve already found out that there is baseband in this phone, in this case, no need to consider if it’s caused by the baseband, mostly the problem is caused by the RFF3 bus of baseband.
1. Split the Logic Board and removed the BASEBAND IC.
3. Reball the BASEBAND IC.
5. Fix back the Logic Board.
Credit to the Professional Tech : Alfred http://igsmrepairtechnology.com