I want the car to be able to contact emergency services, but not to otherwise be able to use the cellular network. Is there a good way to sabotage the eSIM, without otherwise breaking the modem? (This would still allow the car to be tracked via IMEI, but I'm not too worried about that: anyone capable of that is also capable of tracking my actual phone, and anyone buying that data will already know what car I own.)
why do you want your car to contact emergency services? the people around you can do that just fine and very reliably.
How on earth did we survive as a species before our cars could make automated phone calls?