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.

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.

Today, the remaining fob does not let us turn on the car when the fob is on our person; we need to hold the fob up to the button we normally push to start the car. What is going on?

Watch this video to see how to change the battery in your key fob. How to replace car key battery Most key fobs have a little slot you can use to pop them open with a small flatheaded screwdriver ...