Car Alarms

A car alarm is a device installed in a car in an attempt to discourage theft of that car. Most alarms work by making a loud sound. Other alarms disable the ignition of the car, or send a signal to the owner (by way of a beeper) that his or her car is being disturbed. more...

Car alarms are set off by vibrations, tilting of the car (to prevent unauthorized towing), or touching the car. The vast majority of car alarms which sound are accidental. They are caused by the passing of large trucks, the vibration of thunder or people touching the car (as to tie one's shoe on a bumper).

Since most car alarms are accidental, most people in American cities are numbed to the sound of alarms, and do nothing to prevent theft. The New York City Police Department claims that car alarms are actually making the crime problem worse (see their booklet called "Police Strategy No. 5: Reclaiming the Public Spaces of New York," City of New York, New York, 1994) because since nothing is done about the alarms, the general impression is that no one cares about the neighborhood.

Because of the large number of false alarms with car alarms, many vehicle manufacturers no longer factory fit alarms, offering silent—but effective—immobilizers instead. As an after-market fitting, a vehicle tracking system, which allows the police to trace stolen vehicles is considerably more effective. Both of these class of devices cover the event of someone attempting to take the vehicle without consent; but do not cover theft from, or vandalism of, the vehicle.

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