You likely have a problem with the theft deterrent system. Try your extra key to see if that works (the system reads the resistance in the key chip and if it is correct it will allow the engine to start).
If the second key doesn't work, you'll need to find a dealership of an independent shop which specializes in BMW and has the special equipment needed to diagnose the system.
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Saturday, December 14th, 2013 AT 11:14 AM