My X5 has a camera powered by the key power garage door wiring. I have a post on it. I have not added a rear camera yet. I plan to use the heated rear seat relay. It's key powered. It would make wiring a lot shorter. I'll add it on my todo list when a hitch and wiring harness go on.

Any luck with the OEM MAF?

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'06 X5 3.0i - bought @143,123 miles (12/26/20)