> Important: Even after the modem is removed, if you connect your phone to the car via Bluetooth then the car will use your phone as an internet connection and send all the same telemetry data back to Toyota.
How is this the case? I thought bluetooth was just sharing my phone's audio. Why would it allow requests over the internet? Surely there's a way to tell the phone not to give its internet connection to any connected bluetooth device?
I think there are details being left out. But several people in the comments indicate that there is a Toyota app that provides various features. I bet the app implements some proprietary bluetooth service that the head unit connects to and feeds information through. Or maybe they give the head unit a straight pipe to the internet via that service.
There is a bluetooth protocol for cars to piggyback on your phone's internet connection. There was an article about it here a couple of years ago but I've forgotten the name of the protocol, and trying to search for it turns up a lot of irrelevance.
The fix for this is a phone that doesn't implement that protocol, i.e. not Android or iOS.
Is this specific to carplay, or can other bluetooth devices also silently and nefariously hijack your cellular data connection?
The bluetooth protocol includes the ability to network, and share connections like a mobile/personal hotspot.
Older versions of bluetooth may have other networking capabilities.
When reading the article I think he appears to be talking about car play/android auto connection not audio only connections. I think Bluetooth in AA and Carplay is used to configure a local network between the phone and the car to transmit the images to the cars screen. I would assume that that data capability can also be used for the car to communicate with the Internet.