Start with fuses.

Also what year is your vehicle?

Does your vehicle have the 20 pin DLC connector under the hood? I assume the earlier E53 may have the 20 pin DLC connector under the hood.

If so, are you connected to the 20 pin DLC connector under the hood with an adapter cable?

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2008 4.8i Black with Tabacco. Black Y-spoke wheels and shadowline trim.