Remote keyless entry is a system designed to allow or deny access to a vehicle in a way that is similar to a standard car key but without the physical contact. The power door locks and trunk can be locked or unlocked from a distance away from the car for a key-free system. This type of system is known by several different trade names, but most often is simply referred to as keyless entry. The keyless entry system first appeared on the market in the early 1980s and had become widely available by the end of the 1980s.
Keyless entry systems use a radio transmitter (often a key fob or a fob integrated as part of the ignition key) which acts as an electronic key. Inside the car is a receiver that is preset to the same frequency that the transmitter is using. When you push a button you turn the transmitter on. It sends out a code to the receiver, which in turns instructs the system to lock or unlock the vehicle.
The fob oftentimes has several functions built into it. There are buttons that are designated for locking or unlocking doors, releasing trunk lids, unlocking tailgates and other functions. Some of the newer systems will open and close windows when locking the vehicle remotely. Still others contain a panic button, which activates the car alarm or sounds the horn and flashes the vehicle's lights.
When pressing a button on the transmitter, the intended operation is confirmed through the activation of the vehicle's lights and/or through an audio alert.
The range of remote keyless entry devices differs widely between manufacturers.
Some vehicles come with a keyless entry proximity system - also called the hands-free system. This system works by triggering a transmitter function automatically if the key is within a certain distance of the vehicle. With this system, there is no need for the driver to push a button to initiate an action. When you comeÂ within the pre-set distance of the vehicle, the system is triggered automatically and the car will unlock the driver's door. When the transmitter is out of range of the vehicle, the doors automatically lock.
A third type of keyless entry system that is not yet in widespread use is one that is touch activated. When a driver or passenger touches a sensor that sits behind the door handle, the system will unlock the doors. In the future, biometrics may allow complete vehicle security using a touch system with no need for a key or fob.
Any powered system can be controled via these advanced systems, including the windows, sunroof, lights, etc.