Grandstream Networks GSC3516 User Manual page 63

The LED Test is used to test the availability of the four colored LEDs and their intensity. The colors of LEDs available are Green,
Red, Blue, and White.
Certificate Verify
Certificate Verify is used to test the validity of the existing certificate.
Reset Button Test
Reset Button Test is used to test the Reset button, during the test the reset button doesn't trigger a factory reset, this feature
allows the user to check if the button is responding.
GSC3516 LED Test
GSC3506 LED Test
Certificate Verify