Nav System Suddenly "Can't Find Route"
 

I just picked up my G37 convertible (2011) from being serviced, and now the Nav System can't calculate routes. The maps are working, when I enter an address or select a previous destination, the map displays the destination correctly, but it won't/can't figure out how to get there. The screen shows the destination address but then calculates a route to my current location. Before I haul myself back to the dealership - any clues or previous experience? Maybe something I just need to re-set? It's never done this before, even with battery replacements.