The depth numbers listed on the right side of the sonar graph indicate the range of depth that is being displayed on the screen. The normal sonar screen will display the depth range starting from 0 at the surface of the water and continue down the right side until the bottom is reached. They will be reversed when the device is set to Bottom Lock.

Bottom Lock is a feature that will tell the display to zoom into the bottom of the sonar image. The range numbers will then be reversed. The depth range will start at 0 feet at the bottom of the screen and increase going up the side of the screen. The amount of feet that is being displayed can be adjusted. To change the range numbers to normal mode, Bottom Lock will need to be turned off.

To turn Bottom Lock off, please follow these instructions:

From the Home screen select Sonar
Select Full Screen
Press the Menu button
Select Zoom
Select No Zoom

This will deactivate Bottom Lock and display the sonar image in its normal mode.