BMW E46/E39 with a "powered" antenna

Some BMWs before early 2002 have an antenna that is powered by the factory head unit, when you remove the OEM head unit, you remove the power source resulting in sub par radio reception. The fix is to buy a Metra 40-VW53 antenna adapter and the Metra 40-EU20. On the 40-VW53, connect the blue power wire on it to the blue wire labeled "AMP TURN" on the main Dynavin wire harness. This restores power to the antenna and will improve reception. Since the Dynavin has an OEM Fakra style antenna plug instead of a standard aftermarket antenna plug, you will also need the Metra 40-EU20 to convert the standard antenna plug on the Metra 40-VW53 part to the Fakra style plug on the Dynavin.