I have LS 430 2004 Model, When I replaced the battery the Navigation system stopped working, it displayed this message on the screen "please insert correct map disk". Few months back, same problem happened. When I took it to the specialist, he removed my map DVD disk, inserted another DVD (don't know if this cracking DVD or what) for less than one minute, removed this DVD and inserted back my DVD and it worked. I paid him $ 15 to do this.

Anybody knows what to do to fix this problem.

 

Have you tried removing and re-inserting your nav disk?