OK, there is a perfect spot for installing my voltmeter, on my overhead console, there is an empty cover, in the center (I do not have the garage opening switches there). Now, what remains to be seen is, where do I get power from?

The pano roof switch is a logical answer, it seems that it works whenever the key is turned to the on position. However, can someone tell me which is the live wire and which is the ground wire?

Many thanks for your attention.

P.S.: If someone knows from where I can download a full wiring diagram for the car, I would appreciate it.

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John Caradimas
2005 X5 3.0lt diesel
Facelift, Sport packet