A:AnswerDepends on who you are. If you're not the registered owner then there is a mechanism where it'll ring / ping iPhones that it is near to say that this AirTag has been following you. If you're the registered owner, it won't show the level of granularity to pinpoint where exactly in a vehicle it is without possibly ringing the tag.
A:AnswerWhen my tag fell off, it told me it was 4500 miles away from me when I was in Austria and it was in Chicago. It works as long as it's near an iPhone.