If you add to phonebook under ‘own phone number’ +12022243121 with namez (for example MMI), then you will see something
S10, E10:
In phonebook enter +12022243121 as your own phone no. You will see a picture with sun, two palms and greetings.
S15e:
Monitor Mode:
Code: *#7436267*8378# (*#SIEMENS*TEST#)
Hold red phone button until it code disapears.
Menu 3.3.4 Choose frequency.
Menu 3.3.4.1 Automaticaly.
Menu 3.3.4.2 Choose GSM-900
Menu 3.3.4.3 Choose GSM-1800
S25:
Enhanced Full Rate
*#3370# turns on
#3370# turns off
Haft Rate Mode
*#4720# turns on
#4720# turns off.
Languages:
*#0000#+green phone – choose automaticaly
*#0001#+green phone – English
*#0030#+green phone – Greek
*#0031#+green phone – Netherlands
*#0032#+green phone – French
*#0034#+green phone – Spanish
*#0039#+green phone – Italian
*#0049#+green phone – German
*#0090#+green phone – Turkish
How to change PIN2?
**04*old PIN2*new PIN2*new PIN2#
What is my software version?
Menu 8-8-2 press left-softkey when you see IMEI number, or *#06# and then green phone button and then press left soft-key.
How to extend battery life:
IrDA – turn on only when you need.
Turn off automatic network search (6-3)Turn off Vibration alarm.
C25:
Languages:
*#0000#+green phone – choose automaticaly
*#0001#+green phone – English
*#0030#+green phone – Greek
*#0031#+green phone – Netherlands
*#0032#+green phone – French
*#0034#+green phone – Spanish
*#0039#+green phone – Italian
*#0049#+green phone – German
*#0090#+green phone – Turkish
How to change PIN:
**04*old PIN*new PIN*new PIN#
http://wahanaponsel.wordpress.com/2008/06/15/code-rahasia-handphone-gsm-dan-cdma/