I have collected and  listed some secret codes on S60 phones to display various useful information.
To enter theses codes, the phone must be in the idle screen (not in the menu screen). What is idle screen? This is the screen where you see the operator name, date, time, battery level, signal strength and some other stuff. You can switch between idle screen and menu screen using Menu key.

• *#0000# - Display the software version, the date when the software was built and the phone model. In some cases, the phone model is not the one used by marketing. It is the internal model used inside Nokia.
  
• *#06# - Display IMEI (International Mobile Equipment Identify) of your phone.
• *#7780# (*#rst0*) - This will soft reset your phone, all data, like contacts, calendar and notes, are not removed. It will only reset the phone settings, such as profiles, themes and shortcuts. The default lock code is 12345.
• *#7370# - Hard reset, all data, like contacts, calendar and notes, will be removed.
• There is another key combination which is used to hard reset the phone (similar to #*7370). It is useful in some cases, for example when the phone cannot reboot. The trick is by switching off the phone then press and hold Call key (Green key) + * key + 3 key + power button for a couple of seconds. This key combination doesn’t work on some S60 phones (s60 ver1)
• *#2820# (*#BTA0#) - Display the Bluetooth device address of your phone.
• *#62209526# (*#MAC0WLAN) - Display the MAC address of the WLAN adapter. This is available only in the newer devices that support WLAN
• *#67705646# This will clear the LCD display(operator logo).
• *#746025625# Sim clock allowed status.
• *#7328748263373738# resets security code.

All of the key combination doesn’t work on some S60 phones depend on symbian OS Version and S60 platform version

Labels: Tip and Trick