I searched for it but did found. It's my third day without my cell.
I can: Root and install Safestrap, with it i dont have problem.
I try, but did not work: - Codes like *#27663368378#, *#0011#, *#197328640#*.
- Change de modem to MF3,MDL.
Model: SGH-I337 (AT&T)
Android Version: 4.3
Baseband version: MK2
I buy this S4 in EUA and now i need use in Brazil. :/