To tell you the truth, this codes are not that secret since many people know them, and I was reading several articles on the web to solve a problem in an old android and I realized that it could be interesting for you to know these nice codes and here I present one compilation of those that I found more useful.
Code Function
*#06# Show IMEI
*#0*# Phone information menu
*#*#4636#*#* Phone information menu
*#*#34971539#*#* Camera information
*#*#1111#*#* FTA version of the software
*#*#1234#*#* PDA version of the software
*#12580*369# Software and hardware information
*#7465625# Phone lock status
*#*#232338#*#* MAC address
*#*#2663#*#* Touchscreen
*#*#2664#*#* Touchscreen test
*#*#3264#*#* RAM version
*#*#232337#*# Bluetooth address
*#*#2222#*#* Hardware version
*#*#44336#*#* OS version and update data
*#*#197328640#*#* Test mode
*#*#0588#*#* Proximity sensor test
*#*#0289#*#* Audio test
*#*#0*#*#* Test for LCD screens
*#*#1575#*#* Complete GPS analysis
*#*#1472365#*#* Quick test - Quick GPS analysis
*#*#232331#*#* Bluetooth test
*#*#0842#*#* Vibration and screen brightness test
*#*#232339#*#* Wi-Fi test
*#9090# Diagnostic settings
*#872564# USB input settings
*#301279# HSDPA and HSUPA settings
*#*#0588#*#* Proximity sensor test
*#0228# Battery Status
*#0782# Clock test
*#*#34971539#*#* Camera hardware information
*#*#1472365#*#* Test for GPS
*#8736364# Access to the OTA updates menu
*#3282*727336*# Data usage statistics
*#*#0842#*#* Vibration and backlight system test
*#*#273282*255*663282*#*#* Backup of the user's personal files
*#*#273283*255*663282*#*#* Backup all media files
Cc:-
@steemitblog
@steemcurator01
@steemcurator02
@stephenkendal
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