Not sure what is different on the 2011, but I think that either the vehicle recognizes that you have installed the trailer lighting module or not after installation. If it does, lights and PDC work. If it doesn't, then brake lights and/or PDC defeat would likely not work.

The newest version of the hitch install instructions I used had specific flash instructions, unlike earlier versions of the same publication. In my case, I didn't need to flash the X3 based on those instructions. If the instructions for the E70 say it needs to be flashed, and those instructions are the most recent publication, I think that would be more accurate than all of our guessing.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue