devon383,
Classic symptom of (logically ) NO CF card. The card could be missing or not fully seated or corrupt/bad. IMO, the GPS is operating on its base map data which does not include address look up...! To prove that, pull the CF card -- the GPS should act the same as you described.
Try "reading" the CF card (in a Card Reader) on the computer. You should see just a garmin folder, which contains the gmapsupp.img file. If you can read the card in the reader, look into the card slot on the GPS with a small flashlight and see if one or more pins is/are bent out of position. A bent pin usually requires a trip back to Garmin to have that CF card connector replaced. However, if the pins look good, reinsert the card and see if the problem still exists.
Good luck...!