If you have xenons with auto leveling the rear right sensor has 6 wires and separate circuits for both EHC and xenon leveling. The left side sensor has only one circuit so you can't swap them like that.

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E39 530dA -02 M-Sport Messing metallic
E53 X5 3.0dA -06 Sport Stratus grey
E70 X5 40d -12 M-Sport Space grey