Then there is something dramatically wrong with my car, because there shouldn't be one sensor that prevents the car from working entirely. A car kept in good repair should not suddenly and completely stop working. If you're handy, you might even fix whatever is wrong with the car yourself. If my battery dies, I can jump start the car. I had a car once that would fail to start unless you pushed it downhill a bit to reduce the resistance to turning over.

A breathalyzer is often wrong. Diabetes can cause ketosis that will trigger a positive breathalyzer. Someone on the atkins diet could have ketones on their breath. Worst of all, they can be fooled by someone who is drunk and wants to bypass the restrictions, so it's probably not going to actually stop any drunks who are trying to drive.

This is a brand new issue, because you're talking about a device that doesn't exist yet which passively and reliably detects impairment or BAC and then deliberately and completely disables a vehicle with no recourse. I'm in favor of preventing drunk driving, but we need a better solution than "invent a technology that somehow prevents drunk driving." That's not even a plan, it's a vision board. Maybe the device should reduce emissions and provide healthcare, too.