A key fob with remote locking/unlocking and push-button start. A key fob with push-button start and keyless entry that owners can leave in their purse or pocket for virtually all functions.

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.

Press the push button start on your key fob, and hold the button until your engine starts. To turn off your car's engine, follow these steps: Put your vehicle in the park gear.

Push-button ignitions work via the fob, also known as a "smart key," which allows a driver to keep the device in a pocket, purse or other place when unlocking, locking and starting the vehicle.

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.

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