Nokia Universal Codes (Big List), Will work on most Nokia Mobile Phones
(1) *3370# Activate Enhanced Full Rate Codec (EFR) - Your phone uses the best sound quality but talk time is reduced my approx. 5%
(2) #3370# Deactivate Enhanced Full Rate Codec (EFR) OR *3370# ( Favourite )
(3) *#4720# Activate Half Rate Codec - Your phone uses a lower quality sound but you should gain approx 30% more Talk Time.
(4) *#4720# Deactivate Half Rate Codec.
(5) *#0000# Displays your phones software version, 1st Line : Software Version, 2nd Line : Software Release Date, 3rd Line : Compression Type. ( Favourite )
(6) *#9999# Phones software version if *#0000# does not work.
(7) *#06# For checking the International Mobile Equipment Identity (IMEI Number). ( Favourite )
(8) #pw+1234567890+1# Provider Lock Status. (use the "*" button to obtain the "p,w"
and "+" symbols).
(9) #pw+1234567890+2# Network Lock Status. (use the "*" butt
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