The Samsung Galaxy A7 (2018) is a capable mid-range device known for its triple-camera setup and Super AMOLED display. However, beneath the standard One UI or Samsung Experience interface lies a hidden layer of software known as "Service Mode." This hidden layer is accessed via secret codes (also known as USSD codes or dialer codes).
⚠️ Back up your data before using reset codes.
Voltage and Level: Shows the current health and charge state.
This is the most powerful tool for troubleshooting. Once entered, a grid of buttons appears, allowing you to test: Colors (Red, Green, Blue): Checks for dead pixels or screen burn-in.
What are Secret Codes?
If you suspect your phone has a hardware fault, this is the most important code to know.
To use secret codes on your Samsung Galaxy A7, follow these steps:
