I would check the bundle of wires that comes from the door jamb to the door. They flex every time the door is opened, and can become damaged. If the wires are shorting between each other that could explain what you are experiencing.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
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2003 X5 3.0 Steptronic, Premium, Titanium Silver
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