Oh, didn't realise that.
On the o/s/f and o/s/r suspension arms there is a small potentiometer connected between the lower arm and the chassis to measure the height. It clips onto the arm with a little press-on balljoint but can and does come off. You need to remove the wheels to see it and clip it back on if it's come off. My front one used to come off regularly for some reason on my e46 but not happened with my e92 or f10. Principle of operation is identical, however.
Current: 2014 F31 320d M-Sport, Professional Media, Visibility Pack, Reversing Camera, DAB
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