Not sure what you mean by the "CD damaged in collision". This was a passenger side front end fender bender. The only reason I mentioned it was in case there is some sensor located in the front end. Is that what you mean? It is almost as if my GPS can no longer find my current location. Is there some way to reboot the GPS?
As to the GPS not being able to find your current location, the GPS antenna could also have become disconnected. Check your display for the number of satellites you are receiving (your COMAND manual tells you how to do this). If zero satellites, it is an antenna problem (a very different situation from what you first described). There is a splitter in the left side quarter panel; see that all connections are still good. There are a number of writeups on the forum dealing with inability to receive satellites, and also how to re-initialize the system if it needs it, once reception is restored.
The laser head may also have contacted the CD and damaged either the CD or the head itself. This would be especially true if the laser head was "reading" the CD at the time. Check the CD for damage.
If you are in the U.S., test your nav unit by putting in a different Nav CD, setting a destination (as long as it appears on the disc you insert), drive to within a mile of an Interstate, and see if guidance begins. U.S. CD sets for nav systems since the last half of production in '00 have had the entire U.S. Interstate system on each disc. They also show major local roads within a mile or so of the Interstates. That lets you begin, for instance, in California and drive to Miami, without changing discs enroute. It will also let you check your nav reader for proper function.
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