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.

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.

Instead of using a key to turn the ignition or verifying your presence inside a car using a fob, the vehicle will communicate with your phone over Bluetooth.