According to the Help file, you go to Settings-Applications-Manage applications and there will be an icon for the Car Home or Maps app and the Menu should lead you to a reset or clear history button. However, on my Droid there is no icon for the Maps or the Car Home app at this site. Has anyone else run into this problem, and do you know the solution?
Settings -> Applications -> Manage Applications -> 'Menu' button -> Filter -> All
Scroll down the list and it's there. I answered this in more detail here:
I am having trouble figuring out Google Map. I downloaded My Map app and after playing with it, got it to layer "Home" on the map as a base. I think it is really cool to use the satellite and actually "see" my home from above.