A Preferred Sources menu will appear on NMEA 2000 or Garmin Marine Network compatible devices if more than one source of similar information is connected. For example, if two sources providing water depth or temperature are connected, then this Preferred Sources option will show.

In order for the Preferred Sources to show, the software for the Garmin chartplotter must be up to date. See Garmin Marine Device Software Updates for directions on how to update software.

The Preferred Sources option should appear after following this sequence through the menus:

Home Screen
Configure or Settings
Communications
Preferred Sources

There should be an option for depth (and or temperature; if applicable) to allow switching between the preferred source. In cases where the transducer is out of the water and not reading, then there may not be a preferred sources option.

With the GMI 20 instrument and an intelliducer, the instrument will default to the NMEA 2000 Intelliducer depth reading. If the Intelliducer is not reading depth then it will read the depth from the other source.