*#*#4636#*#* phone information
*2767*3855# hard reset
*#*#7780#*#* factory reset
*#*#7594#*#* change end call/power option
*#*#197328640#*#* service mode
*#*#273283*255*663282*#*#* file copy screen (backup media files)
*#*#526#*#* wlan test
*#*#232338#*#* shows wifi mac address
*#*#1472365#*#* gps test
*#*#1575#*#* another gps test
*#*#232331#*#* bluetooth test
*#*#232337#*# shows bluetooth device address
*#*#8255#*#* gtalk service monitor

*#*#0283#*#* packet loopback
*#*#0*#*#* lcd test
*#*#0673#*#* melody test
*#*#0842#*#* device test (vibration test and backlight test)
*#*#2663#*#* touch screen version
*#*#2664#*#* touch screen test
*#*#0588#*#* proximity sensor test
*#*#3264#*#* ram version

codes to get firmware version information:
*#*#4986*2650468#*#* pda, phone, h/w, rfcalldate
*#*#1234#*#* pda and phone
*#*#1111#*#* fta sw version
*#*#2222#*#* fta hw version
*#*#44336#*#* pda, phone, csc, build time, changelist number

note:

• hard reset menghapus semua files & settings di internal memory, atau sama dengan memformat ulang firmwarenya warning! Kalo udah pencet ini langsung hardreset, ngga ada pilihan cancel.
• Factory reset hanya menghapus account, system & aplikasi setting