Your android device is trained a lot by google and it show many tests and many factory tests you do at home. so here I collected few android secret codes which are much useful.
1) WLAN, GPS and Bluetooth Test Android Secret Codes
Codes
Functioning
*#*#526#*#*
*#*#528#*#*
*#*#232339#*#*
WLAN Test.
*#*#232338#*#*
Displays/Shows WiFi MAC address.
*#*#1472365#*
For quick GPS test.
*#*#1575#*#*
Different type GPS test.
*#*#232331#*#*
Bluetooth test.
*#*#232337#*#
Displays Bluetooth device address.
2) Common Android Secret Codes:
Codes
Functioning
*#*#7780#*#*
Factory restore setting
Clear all application and data.
Remove Google account setting.
Remove System, application data and settings.
*2767*3855#
Reinstall the phones firmware.
Used for factory format.
Remove all files and settings including the internal storage.
Reinstall the firmware.
*#*#197328640#*#*
Enabling test mode for service activity.
Used to enter into Service mode.
You can run and change various tests and settings in the service mode.
*#*#4636#*#*
Phone basic information.
Phone usage detail.
Battery information.
*#*#34971539#*#*
Information about mobile camera.
Get camera information.
Note:- Please avoid update camera firmware option
*#*#7594#*#*
Changing the power button behavior.
Enables the direct power off without asking for selecting any option (silent mode, Aeroplane and power off).
*#*#273283*255*663282*#*#*
Create backup to all your media files.
Opens file copy screen where you can backup your media files like (images, videos and audios).
*#*#8255#*#*
For Google Talk service monitoring.
Used to launch G Talk Service Monitor.
*2767*4387264636*
Used to display product code.
*#0228#
Used to know Battery Status.
*#12580*369*
Software and Hardware Info.
*#32489#
Let you know Ciphering Info.
*#273283*255*3282*#
Data create menu.
*#3282*727336*#
Data usage status.
*#8736364#
OTA update menu.
3) Factory Tests:
Coding
Functioning
*#*#0283#*#*
Packet Loop-back test.
*#*#0*#*#*
LCD test.
*#*#0673#*#*
*#*#0289#*#*
Audio/Melody test.
*#*#0842#*#*
Vibration test and Back Light test Device test.
*#*#2663#*#*
Displays Touch screen version.
*#*#2664#*#*
Touch-Screen test.
*#*#0588#*#*
Proximity sensor test.
*#*#3264#*#*
RAM version.
*#0782#
Real time clock test.
*#0589#
Light sensor test.
*#7353#
Quick test menu.
4) Firmware version information:
Codes
Functioning
*#*#1111#*#*
Let you know about FTA SW Version.
*#*#2222#*#*
FTA Hardware Version.
*#*#4986*2650468#*#*
Firmware Info PDA, Phone, H/W, RFCallDate.
*#*#1234#*#*
PDA and Phone firmware info.
*#2263#
RF band selection
*#9090#
Diagnostic configuration.
*#7284#
USB 12C mode control.
*#872564#
USB logging control.
*#745#
RIL dump menu.
*#746#
Debug dump menu.
*#9900#
System dump mode.
*#*#44336#*#*
Shows Build time changelist number.
PDA, Phone, CSC, Build Time, ChangeList number.
*#03#
NAND flash serial number.
*#3214789#
GCF mode status.
5) Other Android Secret Codes:
Codes
Functioning
*#0*#
Galaxy S3 service menu.
##7764726
Motorola DROID hidden service menu.
The default SPC password is six zeroes(000000).
1809#*990#
LG Optimus 2x hidden service menu.
When prompted for a code enter six zeroes(000000).
3845#*920#
Lg Optimus 3D hidden service menu.
When prompted for a code enter six zeroes(000000).
5) PDA and Phone:
Codes
Functioning
*#*#7262626#*#*
Field test.
*#06#
IMEI number.
*#*#8351#*#*
Enables voice dialing logging mode.
*#*#8350#*#*
Disables voice dialing logging mode.
**05***#
Execute from Emergency dial screeen to unlock PUK code.