*#0000# shows the SW version.
*#3370# - Enhanced Full Rate Codec (EFR) activation. It will automatically restart.
*#3370* - Enhanced Full Rate Codec (EFR) deactivation. It will automatically restart.
*#4720# - Half Rate Codec activation. It will automatically restart
*#4720* - Half Rate Codec deactivation. It will automatically restart
*#746025625# - Sim clock allowed status.Enhanced Full Rate will give you much better
sound quality when you enable it. The new Enhanced Full Rate CODEC adopted by GSM uses the ASELP (AlgebraicCode Excitation Linear Prediction) compression technology. this technology allows for much great voice quality in the same number of bits as the older Full Rate CODEC. The older technology was called LPC-RPE (Linear Prediction Coding with Regular Pulse Excitation). Both operate at 13 kilobits.(but you take up more space on the network, so they can charge you more). Talk-time is reduced with about 5%Half Rate will give you bad soundquality, which gives the serviceprovider the opportunity to have more calls on the network, and you might get a lower charge from them. - Will give you 30% longer talk-time. at *#746025625# Sim Clock Stop apparently only works for 3 minuts.
*#92702689# - takes you to a secret menu with 6 choices
1) shows the serial nr.
2) shows when the cel phone was made mmyy
3) shows when the the cel. phone was purchased mmyy
4) shows how many times the cel. phone has been repaired.
5) makes u capebel of transferring user data if u have the gear for it
6) shows how many houres the phone has been on
Another useful tips:
How to reset/reformat a phone,
It may happens that a program corrupts the C: drive of your phone. In such case, some data can be lost of course but, more annoying, some applications may not work or work only partially,...
On a Series 60 based phone, two key sequences will allow to restore your phone to a cleaner state:
-Normal Reset (*#7780#) : Restores ini files from rom but preserves user data (photos, 3rd party apps etc)
-Deep Reset (*#7370#) : This reformats completely the C: drive. All applications and files stored on this drive will be lost and clean default files will be rewritten.
In both case, the phone will ask you a confirmation and you will have to enter a security code (12345 by default).
Files and applications stored on E: drive are not be affected by these sequences.
Useful helps : Full phone formatting a 6600! Here to let everybody how to perform a Full phone formatting on a 6600! If you encounter situation like below on your 6600,
1. Blank screen phone unable to reboot.
2. Phone only able to boot-up to "Nokia" word screen.
3. Install some program but not able to uninstall it after that.
4. Unable to delete unwanted files on C drive. Do a Full phone formatting on your 6600!
as steps below,
1. Make sure you have at least 3/4 charge of battery power left.
2. Backup your contacts list and personal files to MMC memory card.
3. Switch-off your 6600 phone.
4. Press and hold 3 keys; Green dial key, * Star key, no. 3 key on keypad and then press the power on/off to swtich on the 6600 phone. Remember, do not let go the 3 press and hold keys until you see a formatting word screen show!
5. After a few minutes when the Full phone formatting completed, your 6600 will back to original system and factory settting