I was reading on another forum about a guy who made something that plugged in to his cars CAN bus.

On the car, if you reach in the door handle, its supposed to unlock automatically. Sometimes it takes a few tries.

He made something that would detect the door handle activity, and if it didn't see the "unlock door" request "quickly", it would send the door request again.

Now, I'm sure its more sophisticated than monitor the CAN traffic for a "2" and then sending a "3" after a timer, but it's not much more than that.

But the thing is he's using a Raspberry Pi Zero and a CAN bus controller. Basically ~$10 in hardware.

And now you have a machine with a GHz processor and hundreds of MBs of RAM....listening for a "2" so it can send a "3".

Just like Marvin the robot in Hitchhikers Guide.