Yes, when you get a nav coded, it brings it back to full regional specifications. So, for a US-spec car...

• You will get the accept screen
• Short distances will be in feet
• The Emergency function will show up on the main menu
• The Route Magnet feature will go away
• The vehicle ID (VIN, model) etc. will be stored in the nav
• The language selections will include US English

However, you can always do the downgrade/upgrade trick to kick the nav computer back into Euro-mode to reverse the first five changes. (Euro-mode is really a misnomer, becuase the computer really does not revert back to a full Euro state. The nav computer remembers its regional coding and language settings.)

__________________
SOLD
2000 E38 750iL Highline Edition, Upgraded with the lastest 2006 X5 Electronics
MKIV Navigation, 16:9 Display, Bluetooth, TV/Video with Backup Camera, Sirius, and Aux Input