If I am on a call on my phone and enter my vehicle that's it for the call. The phone connects to the BMW bluetooth, but my car doesn't play the call. It's just the radio or whatever was on. My phone is still connected and the timer continues to count, but if I try to use the phone I can't hear the other end and they can't hear me.

How is this handoff supposed to function?

 

It take several minutes for the BT to completely connect and the handshake to be effected. Whenever I need to move to my car and am on a call I alert the parties on the call that I will be AWOL for a time. You should also ensure your cell phone has the most recent firmware installed.

I've made my compliant to BMW, without any resolution; there are lots of posts about the funky BT on these cars. My car s/w is the most current available. Maybe the newer hard disc systems are quicker. For now it's something I'm aware of and accommodate for.