Every car breaks down. It's just a part of life.
And so why would it be any different in a fictional movie? Even so, the cars driven by an actor has the potential to break down at any moment in time.
If you were James Bond, the next step in the process of a mechanical problem would be to repair the automobile.
Now, if you have a flat tire, you are out of luck, because unless you're ready to get down and ruin your suit, you'll have to wait for a tow truck.
But if the problem is a more engine-related issue, the Blue Driver Portable Scanner goes Bluetooth to your smartphone is going to be your best friend, and is able to diagnose the problem in seconds.