Cars have 'secret button' that starts engine even if your key fob dies Around 60 per-cent of drivers with push-button start systems had no idea their car had a hidden emergency start feature.

The keyless car is a marvel of engineering. But how is it that they can start even when the battery in your key fob goes dead? The answer lies in science.

If you're looking to pick up a new key fob, or repair one, you might wonder how long programming it takes and whether or not you can do it yourself.

A 2023 survey found that over 60 per cent of drivers with push-button start systems had no idea their car had a hidden emergency start feature.

Some automakers have even expanded the remote start button's functionality and/or use a different icon — that's why BMW has a diamond button on its key fob, for instance.

If you have a key fob and have ever been curious about the circle arrow button and its function, here's what it means.