Probably best to buy one of the i-bus interfaces, then its a straight forward plug into the cd changer port, and run navcode, easy peasy.

Good luck

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Sept 03, M3, Silver Grey. Retro-fits: Modded Mk4 DVD Drive, OEM Bluetooth, VR Control, Rainbow Speaker Upgrade, Sony SOT Amp, HK Sub, CCFL, Intravee II, NightMode.