Is it possible to add factory navigation to my 2002 BMW 525i?
Yes on that year it is not very hard to retrofit the factory navigation system here are some links that may help you. http://www.bimmerboard.com/forums/posts/479497 http://www.e38.org/bmw_nav_wiring.pdf http://www.e38.org/e38_nav_retrofit.pdf http://www.e38.org/ I would recommend going for a MK4 Widescreen DVD model as they have the ability to be updated with speed cameras and 3D view.
The e38 won't quite get the job done on an e39. It's close but not the same. Here is an OEM parts display that has been highly beneficial to me when searching for OEM parts. http://www.realoem.com/bmw/select.do You may even hit Bavarian Soundwerks up for some how-to videos.
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