One thing I should have mentioned is: read the codes or get the codes read before venturing down what could be an expensive route.
I had similar issues to you (although mine didn't result in the car going into limp mode) and, despite the numerous potential causes (ABS Sensor, battery, steering angle sensor etc), I followed what I thought was a logical route which eventually worked out for me.
See my post here
http://www.e90post.com/forums/showthread.php?t=813999
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F10 530d M Sport, September 2012 Individual Amazonite Silver, Oyster Dakota Leather, Auto, Nav Pro, Bluetooth + USB Devices, Expanded BMW Online, Comfort Seats, Sunroof, Sun Protection Glass Individual Satin Walnut Honey Brown Trim Interior Inside/Outside Mirror with folding and autodip, M Rear Spoiler