other interesting codes are:
* # * * 3 7 2 # FQC (test mode)
* # * * 3 6 4 # Engineering menu
* # * * 2 6 6 * 0 # Set as data COM port
* # * * 2 6 6 * 1 # Set as log COM port
* # * * 7 9 7 # Time to failure timer & Power down code
* # * * 2 2 6 3 * 0 # Set to default Band
* # * * 2 2 6 3 * 1 # Disable GSM Band
* # * * 2 2 6 3 * 2 # Disable DCS Band
* # * * 2 2 6 3 * 3 # Disable EGSM and DCS Band
* # * * 2 2 6 3 * 4 # Disable PCS Band
* # 9 9 9 # which displays the command log
* # * * 8 3 7 # Version info (some roms doesnt have implemented)

*#66*# Set Factory Mode CONFIRMED
*#8375# Show Software Version CONFIRMED
*#1234# A2DP ACP Mode CONFIRMED
*#1234# A2DP INT Mode CONFIRMED
*#0000# + Send : Set Default Language CONFIRMED
*#0007# + Send : Set Language to Russian CONFIRMED
*#0033# + Send : Set Language to French CONFIRMED
*#0034# + Send : Set Language to Spanish CONFIRMED
*#0039# + Send : Set Language to Italian CONFIRMED
*#0044# + Send : Set Language to English CONFIRMED
*#0049# + Send : Set Language to German CONFIRMED
*#0066# + Send : Set Language to Thai CONFIRMED
*#0084# + Send : Set Language to Vietnamese CONFIRMED
*#0966# + Send : Set Language to Arabic

More some codes for reset mobile china
*#77218114#
*#881188#
*#94267357#
*#9426*357#
*#19912006#
*#118811#
*#3646633#

CHINESE MODELS:

default user code: 1122, 3344, 1234, 5678

Engineer mode: *#110*01#

Factory mode: *#987#

Enable COM port: *#110*01# -> Device -> Set UART -> PS Config -> UART1/115200

Restore factory settings: *#987*99#

LCD contrast: *#369#

software version: *#800#

software version: *#900#

set default language: *#0000# Send

set English language: *#0044# Send

set English language (new firmware): *#001# Send