Q: iPhone5 bluetooth not working

Someone in Apple Care told me I need to do that to have Handoff function working properly.

At moment, just with BT switched ON on both devices, whenever I start writing an email on my iPad and I want to carry on the job on my iPhone, I always get "Cocoa Error 4609".

So Apple got it wrong with 4s but right with 5??  If it works with 4s but not with 5, sorry but I do not understand your logic.

I had this problem and contacted Apple Support, it was because my new iPhone and old iPhone were both named "Amanda's iPhone" so if this is the case with you, just change the name of your new iPhone and restart the bluetooth, it worked for me!

General -> About -> Name

It's my first year anniversary without handsfree between my Audi A6 and my iPhone 5 with IOS 8.4.1 As soon as I made the mistake of upgrading to version 8 my phone stopped working. I have done everything possible and thinkable: upgrade every time to a new version, reset everything, delete each time the device from both car and iPhone, factory reset, upgrade MMI on my car, follow Audi's site for interconnectivity via bluetooth with all cell phones makes, follow all kind of discussion groups, contacted Apple, etc. Now I have an old, obsolete Blackberry that does work with no problem. Apple has enormous problems in my opinion in communicating with the outside world: Wi-Fi, Bluetooth. All energies are used in the latest Apple new development and very little energy in basic, security / safety, simple features as bluetooth. I'm not celebrating this first year anniversary, I did not buy the new 6 iPhone and I will not buy the new coming on the 9th of September. Sad, very sad to see a great company drowning in a glass of bluetooth water

I didn't have trouble with iPhone 4s ios updates but I now have iPhone 5 that doesn't link to my Panasonic Link-to-Cell base unit. I did first deregister the iPhone 4s before trying to link the iPhone 5. You mentioned the PIN but my iPhone 5 doesn't prompt me to enter a PIN. I followed the Panasonic manual directions step by step. NEVER MIND! I realized that I wasn't following the Apple instructions carefully, specifically "Tap your accessory to pair" which I found on Set up and use third-party Bluetooth accessories - Apple Support in a post by another person here. So glad it's working!

It DID work by constant pressing on the the headset button, the one that has a phone icon on it! LOL

thank you buddy you're an Apple hero!!