*#0*#Test Menu - in this Test Menu you can test most futures your SAMSUNG Galaxy A02 have, like : LCD Display,Touch,LED light,Front and Back Cameras and much more.
*#0228#Battery Status - here you have every information about SAMSUNG Galaxy A02 battery.
*#0808#USB Settings - by this menu, you can change the way your SAMSUNG Galaxy A02 will be recognized by PC/Laptop when you are connected with USB cable. Modes like Mass Storage,MPT,ADB, etc.
*#1234#Firmware version - you can check here your SAMSUNG Galaxy A02 Firmware Version and Model Name.
*#2663#Advanced Firmware Version menu allows you to check: TSP FW Version, Touch key FW version, MCU/BINFW Version and WIFI Version.
*#0011#Service Mode will let you check some details like Network Connection details, Serving Cell Info.
*#2683662# - Advanced Service Mode this code gives you access to many things in your SAMSUNG Galaxy A02 e.g. you can test things like, 2G3GLTE WIFI etc. and also lots of things to be checked SIM Information, Antenna, All SW Version, IMEI and much, much more enjoy!
SAMSUNG Galaxy A02 secret codes and hidden features - HardReset.info