Car alarm

A car alarm is an electronic device installed in a vehicle in an attempt to discourage theft of the vehicle itself, its contents, or both. Car alarms work by emitting high-volume sound (often a vehicle-mounted siren, klaxon, pre-recorded verbal warning, the vehicle's own horn, or a combination of these) when the conditions necessary for triggering it are met. Such alarms may also cause the vehicle's headlights to flash, may notify the car's owner of the incident via a paging system, and may interrupt one or more electrical circuits necessary for the car to start. Although inexpensive to acquire and install, the effectiveness of such devices in deterring vehicle burglary or theft when their only effect is to emit sound appears to be negligible.

Car alarm siren
Car alarm siren


An early version of a car alarm for use as a theft deterrent was invented by an unknown prisoner from Denver in 1913.[1] This version was manually armed, and triggered when someone tried to crank the engine. A later alarm inspired by an early version of a remote starter was published in 1916.[2] This version had the car owner carry a receiver, which would buzz if the car ignition system was tampered with.


Car alarms should not be confused with immobilizers; although the purpose of both may be to deter car theft, they operate in a dissimilar fashion. An immobilizer generally will not offer any audible or visual theft deterrence, nor require any more input from the driver than from the driver of a non-immobilizer car.

Car alarms can be divided into two categories:

  • OEM (built into the vehicle at the factory)
  • Aftermarket (installed at any time after the car has been built, such as by the new car dealer, an auto accessories store, or the vehicle's owner)

Alarms often come with a mix of features. Remote car alarms typically consist of an additional radio receiver that allows the owner to wirelessly control the alarm from a key fob. Remote car alarms typically come equipped with an array of sensors along with immobilizers and motion detectors.

Keyless remote car alarms are typically based on strong cryptography authentication methods:

Arming and disarming of car alarms


Typically car alarms are disarmed or armed by a remote. The remotes recently use rolling code.

OEM alarms

Almost all OEM alarms are typically armed and disarmed with the vehicle's keyless entry remote. On many vehicles the key cylinders in the driver or front passenger door activate switches, so that when a key is used in the door the alarm will arm or disarm. Some vehicles will arm when the power door lock switch is pressed with the driver's door open, and the door is subsequently closed. Some vehicles will disarm if the ignition is turned on; often when the vehicle is equipped with a key-based immobilizer and an alarm, the combination of the valid key code and the ignition disarms the system.

Aftermarket alarms

Like OEM alarms, aftermarket systems are usually armed and disarmed via remote. Usually they do not have provisions for external disarming from the key cylinder, but will typically have an override switch mounted in a hidden location.


The individual triggers for a car alarm vary widely, depending on the make and model of the vehicle, and the brand and model of the alarm itself (for aftermarket alarms). Since aftermarket alarms are designed to be universal (i.e., compatible with all 12-volt negative ground electrical systems as opposed to one carmaker's vehicles), these commonly have trigger inputs that the installer/vehicle owner chooses not to connect, which additionally determines what will set the alarm off.

Generally, OEM alarms monitor the doors and trunk/hatch for unauthorized entry. On some vehicles this is done through pin switches, mercury switches, or microswitches integrated into the latch. On others, the doorlock mechanisms have switches built into them. Some OEM alarms additionally will trigger if the hood is opened, or if the ignition is turned on. A few systems have a shock sensor which will trigger upon a significant impact to the vehicle's body, such as window glass being broken. Motion sensors monitoring the vehicle's interior are installed in some higher end models.

The simplest aftermarket alarms are one-piece units with a siren and control module. The most common type of sensor is a shock sensor and two wires (12-volt constant power and ground) which are connected to the car's battery. This type of alarm is triggered by vibration transferred to the shock sensor, or by voltage changes on the input (the alarm assumes that a sudden change in voltage is due to a door or trunk being opened, or the ignition being turned on); however it is very prone to false triggers on late-model vehicles with many electronic control modules, which can draw current with the ignition off.

More sophisticated aftermarket alarms are wired into the vehicle's electronics individually. Typically, these alarms have inputs for power and ground, as well as for positive- and negative-switched door open circuits, negative trunk and/or hood circuits, and ignition-switched circuits to detect the ignition being turned on; aftermarket alarms also usually have a shock sensor which may be built into the control module or external to it.

In addition, some aftermarket alarms have provisions for optional sensors (these must be purchased separately). The tilt sensor can sense the vehicle being tilted (alerting to towing). Tilt sensors come in digital or mercury. A digital sensor is more accurate since it sets itself, allowing for the vehicle to be placed on a hill and not cause false triggers. A sound discriminator or glass breakage sensor senses only the sound of glass breaking. Typically, a sound discriminator sensor can be eliminated using a shock sensor. Proximity, infrared, or motion sensors sense motion inside or outside the vehicle; these are typically installed on convertible or T-top vehicles. These sensors are usually adjustable in order to avoid false alarms. For example, a shock sensor will sometimes vibrate due to a loud noise in the area, or an accidental bump to the car from a passerby. Proximity sensors can cause false alarms in parking lots when a passerby is entering or exiting a vehicle parked next to the armed car. These often cause the alarm to falsely sense an attempted break-in.


Car alarm unintentionally triggered by the acceleration sound of a Porsche GT3 RS.

Although car alarms of some kind have been available since the beginning of the automobile era, the dramatic increase in their installation in the 1980s and 1990s coupled with the fact that nearly all car alarms are triggered accidentally (frequently because of high sensitivity settings) means that people who hear them often ignore them.[3] In 1994 the New York City Police Department claimed that car alarms may actually be making the crime problem worse,[4] and there is one account in 1992 of a thief in New York City rocking a car to deliberately trigger its alarm in order to help conceal the sound of a breaking window.[5]

Because of the large number of false alarms with car alarms, many vehicle manufacturers no longer factory-fit simple noise-making alarms, instead offering silent immobilizers.[6] Alternatively, an aftermarket vehicle tracking system can enable the police to trace stolen vehicles. Most police tracking systems require the user to pay a recurring fee, whereas factory immobilizers are included in the purchase price of the vehicle. GPS locating systems enable the owner of the vehicle to lock and unlock, track, and disable the starter of the vehicle online.

Frequently, false alarms occur because car alarm owners use high sensitivity settings. This may be the main reason why loud bass frequency sound (loud music, other cars or motorcycles with loud exhaust systems, thunderstorms, etc.) can set off car alarms. The second possible reason is that some parts of the alarm system may be improperly installed.


  1. ^ "Prisoner Devises Stolen Automobile Alarm". Popular Mechanics. Hearst Magazines: 509. April 1913. ISSN 0032-4558. Retrieved 26 March 2013.
  2. ^ "New Automobile Alarm Calls for Help". Popular Science. Bonnier Corporation: 753. May 1916. ISSN 0161-7370. Retrieved 26 March 2013.
  3. ^ Ilana E. Strauss (16 May 2016). "The Alarming Truth". The Atlantic Monthly.
  4. ^ Police Strategy No. 5: Reclaiming the Public Spaces of New York, New York City: New York Police Department, 1994
  5. ^ Cooke, Patrick (2 November 1992). "Noises Out: What It's Doing to You". New York Magazine. Retrieved 19 May 2016.
  6. ^ Alarmingly Useless: The Case for Banning Car Alarms in New York City Archived April 14, 2010, at the Wayback Machine

See also

2.4 GHz radio use

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Audio Analytic

Audio Analytic is a British company that has developed a patented sound recognition software framework called ai3 which provides technology with the ability to understand context through sound. This framework includes an embeddable software platform that can react to a range of sounds such as smoke alarm & CO alarms, window breakage, baby cry and dogs barking. Aimed at consumer technology, Audio Analytic's software can be embedded into a wide range of intelligent devices in the home, out and about, or in the car. It is hardware agnostic and designed to run on-device and not in the cloud.

The company was based on University PhD research with seed investment from EEDA (East of England Development Agency) and local Angel investors.

The company’s investors include Cambridge Angels, Rockspring, Martlets, Cambridge Investment Capital and IQ Capital Partners.

Car Alarm (album)

Car Alarm is a 2008 studio album by The Sea and Cake, released on Thrill Jockey.

Car Alarm (disambiguation)

A car alarm is an electronic security device for vehicles

Car Alarm may also refer to:

Car Alarm (album), 2008 album by The Sea and Cake

"Car Alarm", 2007 TV series episode from Kim Possible

Did It On'em

"Did It On'em" is a song by American rapper and singer Nicki Minaj. It was written by Minaj with J. Ellington, Safaree Samuels, and Shondrae "Bangladesh" Crawford, who produced the track. The song served as the sixth single from her debut album, Pink Friday, in the United States.

The song has a distinct sound when compared to the rest of the tracks on the album as it contains a harder, "massive, ungainly" beat, reflecting her prior work on mixtapes. It also features hi-hats in "overdrive" and multiple synth patterns sounding as if a car-alarm siren was going off. Lyrically, Minaj delivers explicit phrases talking about winning over her competition.

"Did It On'em" reached number forty-nine on the US Billboard Hot 100, and reached #3 on the US R&B/Hip-Hop Songs and #4 on US Rap Songs charts. A music video was released for the track, featuring Minaj behind-the-scenes and performing on the I Am Still Music Tour.

T-Pain and Lil Wayne's collaboration album, "T-Wayne", released on May 18th, 2017, uses this beat on the song "Breathe".

Employee Polygraph Protection Act

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Under EPPA, most private employers may not require or request any employee or job applicant to take a lie detector test, or discharge, discipline, or discriminate against anybody for refusing to take a test or for exercising other rights under the act. However, the act does permit polygraph tests to be administered to certain applicants for job with security firms (such as armored car, alarm, and guard companies) and of pharmaceutical manufacturers, distributors, and dispensers. The law does not cover federal, state, and local government agencies.

In addition, employers are required to display a poster in the workplace explaining the EPPA for their employees.

Everybody (The Sea and Cake album)

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Ford Falcon (ED)

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Henry Bean

Henry Bean (born 1945) is an American screenwriter, film director, film producer, novelist, and actor.

Most famous as a screenwriter, Bean wrote the screenplays for Internal Affairs, Deep Cover, Venus Rising, The Believer, Basic Instinct 2 and Noise. The Believer was awarded the dramatic Grand Jury Prize at the 2001 Sundance Festival and the Golden St. George at the 23rd Moscow International Film Festival.Bean, who is Jewish, also acted in The Believer, and was a producer on Deep Cover and Noise. He was the director for The Believer and Noise.

Bean is also the inspiration for the protagonist of Noise. He was so tired of constant noise around him and his home in New York that he decided to take the law into his own hands. If a car alarm was going off and the owner of the vehicle didn't rectify the situation, Bean would break into the car to disable the offending car alarm. Bean was eventually arrested and jailed. He admits to doing it a few more times since.


An immobiliser or immobilizer is an electronic security device fitted to an automobile that prevents the engine from running unless the correct transponder car key (or other token) is present. This prevents the car from being "hot wired" after entry has been achieved and thus reduces motor vehicle theft. Research shows that the uniform application of immobilisers reduced the rate of car theft by 40%.

Kanes and Abel's

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The series depicts the adventures of Veronica Mars (Kristen Bell) as she deals with life as a high school student while moonlighting as a private detective. In this episode, after finding out about Abel Koontz's (Christian Clemenson) daughter, Amelia DeLongpre (Erin Chambers), Veronica tracks her down and tells her that the Kanes are paying off her father. Meanwhile, Veronica investigates the mysterious harasser of Sabrina Fuller (Megan Henning).

List of Kim Possible episodes

The following is a list of episodes for the Disney Channel series Kim Possible, which aired from June 7, 2002 to September 7, 2007, with four seasons, 87 episodes and three TV movies produced.

Luis Gispert

Luis Gispert (born Jersey City, New Jersey, United States, 1972) is an American sculptor and photographer, living and working in Brooklyn, New York. Gispert earned an MFA at Yale University in 2001, a BFA in Film from Art Institute of Chicago in 1996, and attended Miami Dade College from 1990 to 1992.

Luis Gispert creates art through a wide range of media, including photographs, film, sounds, and sculptures, focusing upon hip-hop, youth culture, and Cuban-American history. Some of his sculptures incorporate objects identified with hip hop, such as turntables, chrome tire rims, and boom boxes, into functional designs usable in other manners, such as furniture. He first rose to fame due to his well received Chearleaders set of art photographs which he started in 2000 - several of the pics feature chonga style women, and helped to establish chongas as a Miami icon, comparable to "ghetto fabulous" images. His installation art graced the 2002 Whitney Biennial at the Whitney Museum of American Art, and has been exhibited internationally at galleries and museums such the Brooklyn Museum of Art, and the Studio Museum in Harlem in New York, Art Pace in Texas, the Museum of Contemporary Art, North Miami, the Contemporary Arts Museum Houston, Palazzo Brocherasio in Turin, and the Royal Academy in London. Gispert has also participated in several exhibitions with high-profile commercial galleries including Gagosian Gallery, Andrea Rosen Gallery, and Deitch Projects in New York. He is represented by Mary Boone Gallery in New York, Rhona Hoffman Gallery in Chicago, and Moran Bondaroff in Los Angeles.

Gispert describes the first ten years of his career as a period during which he underwent a personal transformation in his attempt to comprehend why certain objects and events strike him physically and emotionally. Always, there is the push- and-pull between seduction and aggression in his work that inundates the viewer’s senses. His photographs, videos, films and sculptures are complex, composed arrangements that delve into the familiar and the unknown, the mainstream and the marginalized, to expose and address the various subcultures that infiltrate the mainstream. These subjects also provided him the means to explore the sheer aggressiveness and excessiveness of the hip hop ornamentation or the effusively decorated interior of his immigrant family’s homes. Similarly the volume of the rap lyrics lip-synched by a cheerleader in Can It Be That It Was All So Simple Then, 2001, or the unnerving scream of a car alarm mouthed by another cheerleader in Block Watching, 2002, is overwhelming.

In 2011, the Feminist art collective Go! Push Pops performed Block Watching Remix at the Moore St. Market in a show curated by Michelle Lopez during Bushwick Open Studios remixing footage of Luis Gispert's original 2002 Block Watching video. In 2013, Luis Gispert invited Go! Push Pops to perform Block Watching Remix during the Brooklyn Museum's Annual Artist Ball.His most recent photographs of landscapes viewed through the windows of customized vehicles achieve the widescreen grandeur of CinemaScope film and provide the viewer the sensation of occupying the driver’s seat. He shot hundreds of sheets of film for each landscape in an attempt to capture the perfect vista, but ultimately collaged various details to produce landscapes that most closely adhered to his ideal.

Gispert’s cheerleader series of lush, color photographs depicting cheerleaders accessorized with the hip hop gold chains and jewelry, first brought him to the art world’s attention. Although this series was perceived as a reference to popular culture and cultural identity, Gispert approached the subject from the perspective of Baroque religious paintings depicting levitating saints at moments of epiphany and the conventions of sports photography, which established the iconic image of the sports hero in mid air. The cheerleader photographs were achieved with cinematic techniques and methods to produce special effects, most notably the green-screen. Gispert used a long exposure to photograph his models suspended on wires in a chroma-key green room. In movies, actors play against the green background, which is typically superimposed onto another backdrop to complete the illusion. However, Gispert retained the green field to reveal the artifice.

Filmmaking has played a major role in Gispert’s career. He has consistently contrasted films that use the syntax of cinema as exercises in the manipulation of sound, image and film time, as in Stereomongrel, 2005, and Smother, 2008, with raw, aggressive videos that deliberately contradict film conventions. Gispert has used elements of destruction to designate the end of one phase of his career and the beginning of another. He always approaches new projects by trying to work himself out of a problem. This occasionally requires the obliteration of the past and has manifested itself in a sculpture composed of all the props and hip hop ornamentation that he used in his Cheerleader series or the fictitious baptism of a pet dog (representing himself as a child) by fire in order to liberate his creativity in his film “Smother”.

Other works include films such as Stereomongrel.

Michael Winslow

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Oddville, MTV

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misadventures in the backwoods of Canada.

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Car interior


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