Remote keyless systems come as standard or as an option in 70% of cars made today. They consist of a key fob transmitter or a remote and a receiver in the vehicle. To work, they need a frequency, which is unique to them so they can communicate. Due to the security sensitivity of this system, it is regulated by Government agencies in many countries across the world.

Please follow link below to read more:
https://www.spotdem.com/2020/11/28/how-to-know-your-car-key-remote-security-frequency/

American, Canadian etc 315 MHz, European etc 433mhz

baconline:
American, Canadian etc 315 MHz, European etc 433mhz

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