BMW BM53 Part Numbers: http://bimmerboard.com/forums/posts/694974/

BMW BM53 Pin Diagram: http://www.m5board.com/vbulletin/attachments/e39-m5-e52-z8-discussion/138472d1311002003-car-stereo-experts-please-help-new-gen-bm53-pinout.jpg

BMW Auxiliary Audio Input Part # 82110149390 (For E39’s without Navigation)- DIY Below in “Helpful Links”

BMW Auxiliary Audio Input Part # 82110149391 (For E39’s with Navigation)

*Note: If you have a navigation and a vehicle production date before 09/2002 then you could get either one because you have to remove the three wires from the connector anyways.

Extra Helpful links:
http://www.bavauto.com/Assets/inst_pages/ins376.pdf

http://e39source.com/archives/880 (DIY for models without Navigation)

Check out our sister E39Source website: http://www.E39Source.com

BMW E65Source: http://www.youtube.com/E65Source