Like anything else relying on a battery, you car key fob can die—often at the worst time. Thankfully, these batteries are easy to replace.

New key fobs must be programmed with codes that the vehicle has to read before it unlocks the door or allows starting the engine.

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 ...

And that’s just for the fob. Add another $50 to $100 to get replacement fobs programmed to work with your car and to have a new mechanical backup key made. The key fobs for European cars and ...

“The cost to replace the latest key fobs can run anywhere from $50 to as high as $400 depending on the brand,” says Consumer Reports automotive analyst Mel Yu. And that’s just for the fob.

Learning how to change the battery in a Toyota key fob isn't difficult. Whether you have a new or old model, we'll show you how to do it step by step.

But maybe you’ve experienced the downside: The cost to replace the latest key fobs can be as much as $400 depending on the brand. Then add another $20 to $130 to program it to work with your car.

Audi key fobs have varied slightly between different models over the years, but the process to replace batteries is relatively similar and simple for each one.

Just know that most customer-programmable key fobs will require two current working keys in order to program the new one. RELATED: How to replace your key fob | Your key fob may have hidden features ...

Of course, all hope is not lost because this usually just means the battery in your key fob has died and needs to be replaced. And there's no need for a trip to the dealership to do it as it’s ...

For added convenience, a mobile locksmith can replace many fobs, programming and cutting the keys right in your driveway. And did you know your fob is hiding a secret?