Your radio has 0 control over an Engine. Or at least, shouldn't.
Source: Connected Car is my day job.
First of all, many manufacturers market remote engine kill as a subscription service.
Second, many cars use CAN busses and connect the radio to it. That makes it very easy for the radio to interfere with crucial functions, like braking.
The CAN bus uses realtime time multiplexing for congestion control, so it is very easy to target traffic from a particular device subsystem, even accidentally.
Sources: search for “can bus vulnerabilities”. Also, a ~2012 GMC I used to own had a bug in the radio firmware that caused the ABS system to stay on when the engine was off, which ran down the battery overnight.
On my current Dodge, there is a recall where the head unit firmware leads to confusing semantics around “park” on the transmission, and a separate firmware update where it refuses to disengage cruise control.
On recent Ford mustangs, the radio can display all sorts of engine statistics, and tune the engine in real time.
European luxury cars are even more integrated on this front, and have sport modes where the radio changes the response curves for the engine, steering, transmission and suspension.
The first generation Prius had the engine control computer physically inside the radio.
That covers the major car manufacturers across three continents.
Wow, that's a bad one.
Oh, subscription service.
Not GPS signal.
I'm completely right.
From the article:
>The hacker, who goes by the name L&M, told Motherboard he hacked into more than 7,000 iTrack accounts and more than 20,000 ProTrack accounts, two apps that companies use to monitor and manage fleets of vehicles through GPS tracking devices. The hacker was able to track vehicles in a handful of countries around the world, including South Africa, Morocco, India, and the Philippines. On some cars, the software has the capability of remotely turning off the engines of vehicles that are stopped or are traveling 12 miles per hour or slower, according to the manufacturer of certain GPS tracking devices.