Smart keys for cars have almost entirely phased out regular keys. Though not perfect, smart keys have a lot of benefits, and they work in an interesting way.

Replacement usually costs around $125. Transponder key. A computer chip-based ignition key that leverages a wireless connection to validate that the key has the proper code to turn on the vehicle.

Hitag transponders have been used in a wide variety of car keys as a protective measure against hot-wiring and theft. They’re also a reason why it’s a lot more expensive to get car keys ...

Drivers will soon see their long-held I-PASS transponders replaced with stickers from the Illinois Tollway, but will that mean your old transponder won’t work?