Few Secret Hidden Codes In China Mobile Phones

As we all know Chinese mobiles are getting BIG market in India and other countries. Here I'm sharing a few secret service codes for these Chinese mobiles. 

None of them was tested by me but all codes should work because these codes have been taken from a respected mobile manufacturer company:
Enter into Engineering Mode: *#110*01#
Enter into factory Mode: *#987#
Restore Factory Settings: *#987*99#
Check Software Version: *#900# OR *#800#
Default User Codes: 1122, 3344, 1234, 5678
Change LCD Contrast: *#369#
To Enable COM Port: *#110*01# -> Device -> Set UART -> PS Config -> UART1/115200
Codes to Change Screen Language:

• *#0000# + Send : Set Default Language
• *#0007# + Send : Set Language to Russian
• *#0033# + Send : Set Language to French
• *#0034# + Send : Set Language to Spanish
• *#0039# + Send : Set Language to Italian
• *#0044# + Send : Set Language to English
• *#0049# + Send : Set Language to German
• *#0066# + Send : Set Language to Thai
• *#0084# + Send : Set Language to Vietnamese
• *#0966# + Send : Set Language to Arabic