I imagine you could do this by creating a Faraday Cage of some sort around the antenna that would phone home.
In my old car, the BMW i3, I was part of the Reddit sub there and many of us were upset because we had 3G radios in the car that were getting disconnected which meant our smart features would no longer work. But someone was able to replace the 3G modem for a 4G modem somehow. So it may be possible if you can find that component and rip it out or find a way to replace it with a defective part instead, for example.