This blog show you how to enter these secret menu.
They are entered in the main menu shown below:
1. Searching satellite menu
This mode is useful when your GPS seems to be slow in acquiring the satellite reception. This allows you to see how the process happens.
This is entered by just touch and hold your finger down on the reception bar on the top left corner as shown on the picture below.
After touching and holding down your finger on the icon for at least 5 seconds, the following screen will be displayed.
2. Diagnostic menu
I believe that this mode is used by Garmin themselves to find out more information on your unit when you send it back for RMA.
It gives vital statistics about your GPS unit and helps in failure analysis.
It can be entered by touching on the battery icon and hold down for at least 5 seconds as shown below.
Once that is done, you will enter the diagnostic mode.
The following picture shows the first page. This is also the page where u exit the diagnostic mode by tapping on the exit button.
When you tap the next button, it will proceed to the next screen, this screen shows some hardware information.
Tap on the next button to cycle along the diagnostic tests... the following show some graphics diagnostic test.
Touch on the next button to go to the next test! There are quite a few diagnostic test built in.
Once you are done, cycle back to the first page and tap the exit button to leave the diagnostic mode.
The GPS unit will then reboot and you will be back in normal mode again.