similar issue with motorola headset
my iphone6 was not able to see my motorola S10-HD headset, until I was able to flush the data from the headset.
a simple reset of the headset did NOT work.
I had to trigger it to flush all data related to prior binding with my iphone5.
Only then could iphone6 see the headset and successfully bind with it.
to trigger the flush of the data in the headset, while the unit was powered up i held the + button and the pwr button at the same time and then the status light went blue.
then pwr cycled the headset one more time, it came up again with blue status light indicating ready to bind. At that point i turned on bluetooth on iphone6 and was able to bind with the headset.
So if there is a way to flush the data from the car, i definitely would be looking for that sequence.