Sounds like your in navigation mode, if it's a purple line (On the 76Csx it's purple) then your GPS is trying to tell you how to get home! Just go to the map page, hit menu, then stop navigating. If you're already home, and you have satillite fixed, and you still have this, then I don't know what it is.
EDIT: Maybe it's telling how to get to the end of that trip, eitherway, try the above.