Ziatron found a more reliable solution than using Bluetooth.
I found that the Bluetooth interface is not reliable.
I have since changed to a hardwired dock connector in all my cars. These ALWAYS work.
Just about any car audio shop can install these at a low cost.
They are unaffected by firmware updates, and they charge my iPhone and iPod at the same time. So when I get out of my car I have a fully charged iPhone.
Go hardwired, it will ALWAYS work.
Something like: http://www.bestbuy.ca/en-CA/product/geek-squad-universal-play-charge-solution-for-ipod-car-install-kit-gsc70a-in-store-only/10131667.aspx