*#304*19980722# Set ON engineering mode
*#307# OK Engineering test mode
*#311# OK Phone code changed to default code
*#301# OK Full keypads functional test
*#303# OK Set default language to english
*#304# OK Set OFF engineering mode
*#402# OK Adjust display intensity/ contrast
*#403# OK List the manufacturing informations
19980722 OK Master unlock code for phone and simlock
*#06# Display imei
*#300# OK List the software and hardware version
*#302# OK Accoustict test
*#3370# Enhanced full rate
*#0000# OK Settings saved, restore set phone to default language