Bluetooth connection to my vehicles initiates phone call

[iMore Question]

I have an iPhone 5C running iOs 10.1.1. When I enter my vehicles, the phone connects to the vehicle via Bluetooth, but immediately attempts to initiate a phone call with no action by me. I need to "end the phone call" even though I never initiated one. This happens in two different vehicles, and seems to have started when I updated to 10.1.1 or perhaps 10.1. Is this a software issue or do I have an errant setting?