Remote keys transmit a coded signal

In the early nineties, the first remote keys replaced the less reliable infrared technology. They also possessed a key bit, i.e. a classic (folding) key. Later, the first remote keys without key bits and with an electronic ignition lock came onto the market. They were inserted into a corresponding holder rather than a classic ignition lock. To start, you simply pushed the "key” in.

Remote keys are still common technology today and their range of functions has been continuously developed. Using a frequency of 433 or 434 MHz (Europe), they send an encrypted signal to the comfort control unit, which controls the vehicle doors, for example. After pressing the corresponding button on the key, the door locks open or close via an electric actuator. In addition, the immobilizer, which has been mandatory for all newly registered vehicles since 1998, is deactivated using a transponder in the key and individual coding when starting the engine. The engine can be started using the ignition lock.