One of the common steps for this is to park the car in an open area for 10 minuts (or so) so that the MKIV can download the almanac and re-sync with the satellites.

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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