Keyless entry system

A keyless entry system is an electronic lock that controls access to a building or vehicle without using a traditional mechanical key. The term keyless entry system originally meant a lock controlled by a keypad located at or near the driver's door, that required pressing a predetermined (or self-programmed) numeric code for entry. These systems, having evolved into a hidden touch-activated keypad, are still available on certain Ford or Lincoln models.

The term remote keyless system (RKS), also called keyless entry or remote central locking, refers to a lock that uses an electronic remote control as a key which is activated by a handheld device or automatically by proximity.

Widely used in automobiles, an RKS performs the functions of a standard car key without physical contact. When within a few yards of the car, pressing a button on the remote can lock or unlock the doors, and may perform other functions. A remote keyless system can include both a remote keyless entry system (RKE), which unlocks the doors, and a remote keyless ignition system (RKI), which starts the engine.

One of the first introductions was in 1980 on the Ford Thunderbird, Mercury Cougar, Lincoln Continental Mark VI, and Lincoln Town Car, which Ford called Keyless Entry System (later renamed SecuriCode). It was a keypad on the driver-side exterior door above the door handle. It consisted of a keypad with five buttons that when the code was entered, would unlock the driver's door, with subsequent code entries to unlock all doors, and the trunk. Nissan offered the same technology on the Nissan Maxima and Nissan Fairlady beginning in 1984, essentially using the same approach as Ford, with the addition of being able to roll the windows down and open the optional moonroof from outside the vehicle on the door handle installed keypad on both the driver's and front passengers door.

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