Some secret codes for NOKIA phones

These 3 codes work on 90% of Nokia phones;
*#06#=Display the IMEI (Standard GSM command, works on all phones)
*#0000#=Display the firmware version and date
*#92702689#=Here you can view the S/N and the IMEI as well as the life timer (newer models). The date the phone left the factory and the date it was purchased. If your phone has been repaired the date of the repair is also visible. You will need to turn the phone off to exit this menu. Newer phones simply require you to press ok.

The following codes are specific to older series 40 phones;
(Entering the following codes will restart the phone)
*4720#=Activates Half Rate, Half Rate is 5.6kbit/s and uses half the bandwidth at the cost of call quality. Network operators often activate half rate on overloaded towers during peak times to save costs.
#4720#=Deactivates Half Rate
*3370#=Activates Enhanced Full Rate, EFT attempts to match wire quality. The calls are 12.2kbit/s and are not supported by all operators. It is compatibale with the hightest AMR mode.
#3370#=Deactivates Enhanced Full Rate
*#746085685#=Display the SIM clock status

The following codes are phone specific or phase related;
*#7220#=Activate the GPRS PCCCH support (Packet Common Control Channel)
*#7230#=Deactivate the GPRS PCCCH support
*#7760#=Display the manufacturing serial number

This only works on the 3310 and 3330;
*#67705646#=Clear the operator logo, the logo will be reset to the default network operator logo.

The following codes work on newer series 40 & series 60/80 phones;
*#2820#=Display the Bluetooth MAC address (Phone must have a built in bluetooth adapter)
*#7370925538#=Reset the mobile wallet (Phone must have the mobile wallet feature)
*#7370#=Soft-format the memory (Symbian)
*#7780#=Reset to factory defaults, confirmation required (also known has a Hard-format), all phone contents will be wiped clean

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