For cars with a push-button start, however, all you have to do is physically put your dead-battery fob in a designated location, and the button will still work.

In many cases, a fob-only key does more than simply lock and unlock your car. It's also tied to your security system, and sometimes your windows, doors, and liftgates.

One other type of vehicle that typically doesn't have a remote start button on its key fob is a fully-electric one — but it may come with something even better.