Yes but I would force the unit into the Simulator mode. That way you can mark waypoints and have the unit remember them: Power the unit on and while it is showing the title screen (“Humminbird 798ci HD Si”) press the VIEW button, then select “SIMULATOR”. The Simulator that the unit will automatically go in to without the transducer connected will not remember any changes or waypoints when powered off but manually forcing it into this version of the Simulator will.