I discovered a new trick with my 05 X5 today. Don"t ask me how it works but it does!! If you put the metal part of your key touching your chin it will extend the locking/ unlocking range of the key fob. (Hold the key vertically with tip of metal touching your chin) I am able to lock and unlock from so far away by doing this. I know it sound like an urban legend but it really works!! Go try it!!