It could be a bad lock actuator. I think both SuperGreg and I have had that part go out. Mine would repeatedly click whenever I pushed the button to unlock it. It sounded like a rapid "click-click-click-click-click" sound. Your symptoms are not the same but I mention this because that part has gone bad on a couple of our X5's so it might be the case with yours, it's just showing different symptoms.

Word of warning: If it is that, the mechanism is part of the upper hatch handle and that part needs to be ordered and painted since they come only primed. Alot time for this and advise your dealer.

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