I have a 2012 X5 E70 xDrive3i. A few months ago my CA stopped working to unlock the doors. Still works for starting the car. I started looking around on here for solutions. I've seen all sorts of things, some I tried some I haven't. These things were tried but did not work:

• Replaced the battery on the fob.
• Tried the other fob
• Used the key to open the car, put the fob in the slot, start the car, stop it, start it again, stop it again. (someone said some combination of doing this re-syncs the fob to the car)

I didn't find any fixes and decided to live with it and next time I took it in to the mechanic I'd have him figure it out. Then, a couple weeks ago, during a very hot day (94 degrees) it started working again. Worked perfectly. It continued to work for about four or five days. Then, it just stopped working again.

I don't know if the heat had anything to do with it or if it was something else. But it clearly isn't the door handles (as one member suggested).

Has anyone had this experience? Has anyone figured out exactly what the deal is?