You will need either the nav computer or a TV module to actually run the screen and interact with your car's other components (OBC, radio, telephone, etc.) So, you might as well do the full nav retrofit, even if you don't care about the nav function, because it will make the system complete.

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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