It's not necessary to reset settings if you delete your iPhone from the car, go to bluetooth in your iPhone, forget the device, sign out of iCloud, power cycle your iPhone, sign back in, and then pair the phone. ...Some users are getting it to work by pairing the phone more than once.
Resetting settings should always be a very last resort.
I've solved many issues by giving my iPhone a power cycle. When putting a whole new iOS on or restoring and setting up as new, sign out of iCloud first. Things work better if you either sign out of iCloud before upgrading from a full iOS version to a new one, or, after upgrading, sign out of iCloud, power cycle the phone, then sign into iCloud. Apple tries to make things work without having to do this, but, these are still desktop computers shrunk into a small device, it still has similar glitches that computers have, or, rather, had a decade ago. Smart Phones are still a relatively new tech, not perfect. Too many people expect everything to work the same as before, but, if you go from windows 7 to windows 8 or Mac OS X 10.8 to 10.9, things are not always going to be smooth, it's just the way it is whith computers (it's the same with iOS 7 to 8 or iOS 6 to 7.)
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To the editor of MacRumors: you could save a headache, and a bunch of "how do I get iOS 8.1" comments if you'd post correctly:
"Update: According to some users who have installed iOS 8.1, the new update fixes the problems with Bluetooth."
should read:
"Update: According to some developers who have installed the iOS 8.1 developer preview, the new update fixes the problems with Bluetooth."
iOS 8.1 is not yet available for public consumption.
You guys need to step things up, I'm starting to look elsewhere for Mac/iOS information/news/forums, because, this is becoming more like a blog, losing your edge.
I did try unpairing, deleting the phone, signing out of iCloud..... etc then repairing and it did not work. I scoured the forums and spoke at length with apple and this was the only thing that worked