I've noticed today that it will connect to the car, but the bars will not change until I wake up the phone.
For example, under the garage I didn't have any bars. When I left the garage, I usually get full bars, but this time it didn't change. I drove for about 1/2 mile and it was still the same. I pulled out my phone, and as soon as I touched the power button, it was fine.
Tested it again later and same thing, but opposite issue. I had 5 bars when I started the car, and watched it for a few miles.. still 5 bars. When I touched the power, the bars started to move as usual.
I'm wondering if this started after the update, or if it's been happening all along. I really don't know.