How to find hidden service test menu for Samsung galaxy S6, S5, S4, A7, A5, A3

The Samsung Galaxy Service Test menu has two options for testing.

Step 1 | TEST MENU - 1

Enter #7353# in the dialer app.

You will then have access to system diagnostics for various components.
This includes checking the status of sensors such as Light and Proximity, Accelerometer, Touch screen, and Main Camera.

Step 2 | TEST MENU - 2

Enter #0# in the menu.

This menu is identical to the previous one, with the same options and layout.