Have you ever wondered how your car security alarm works? Contrary to what you might think, car alarms are actually pretty simple devices theyre just a set of sensors connected to a siren.

A car security alarm typically has six parts a siren (the device responsible for making the noise) and five sensors (window, door, pressure s, shock, motion and tilt sensors). The simplest car security alarms work mechanically if someone tries to force the door open, for example, the car door sensor sends a signal to the siren, which in turn makes loud sounds. The technology behind door sensors is actually the same technology used in your refrigerator. Notice how your refrigerator lights turn on when you open the door and turns off when you close it? Both technologies are actually simple circuit systems when someone forces the car door open, the spring pushes the button open and closes the circuit, sending electricity the alarm and siren. Most car security alarms systems have very useful accessories such as a radio receiver for wireless control from a key, and backup batteries that allow alarms to work even when the main power source gives up. Most car security alarms have sirens that are capable of creating distinct sounds so that the owner can pick out a sound pattern and be able to tell if it is his or her car thats sounding an alarm.

The most recently developed car alarms offer features that promise to deter car theft more effectively. Among these new features are small computers that are designed to outsmart thieves. When an intruder cuts off the main power source of the car alarm system to prevent it from sounding off, the computer (powered by a hidden battery) triggers the siren to sound the alarm.