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.

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

How to Replace Your Car's Key Fob Consumer Reports looks at what you should know before heading out to find an expensive new key fob.

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.

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.

What should you do if your key fob stops working? Don’t be in a rush to shell out hundreds of dollars to replace it.

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.

In this primer on how to replace a car key fob, Consumer Reports says getting another high-tech key fob can be a pricey proposition.