So I'm having the same issue with my iPhone 6 running on iOS 8.1 .
Here's what I've found to be true:
When my iPhone is severely drained of battery (oddly enough the time when I need to plug it in the most), it gives me the error message
However I put it to the test, I don't get the error message with my battery above 60 percent.
I also have found - and oddly enough never needed to use it before- that my Bluetooth does not connect to my phone.