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Automobile Theft Prevention

With so many vehicles lost every year, it's easy to think that there’s nothing to be done to prevent cars from getting stolen. Take a look a look at these important crime prevention tips to prevent cars from being stolen and learn how to protect your car from becoming a victim of automobile theft.

It may be hard to believe, but hundreds of thousands of cars are stolen every year resulting in losses extending into the billions of dollars. Many vehicle thefts could have been prevented had the owners taken some basic security measures. This report outlines the measures that you can take to protect an automobile from being stolen.

Automobile Theft Prevention Measures

Other than thefts committed by professional car theft rings, motor vehicle thefts can be prevented. As indicated by the FBI statistics on arrests, a number of motor vehicle thefts are perpetrated by teenagers. Basic security measures can usually stop these unsophisticated thieves. The following information outlines the steps that can be taken to make an automobile less vulnerable to theft and, in the event it is stolen, to aid in its recovery. Many of the measures outlined apply to other types of motor vehicles as well.

Situational Awareness

While newer cars are more likely to be stolen, do not be careless because the car is old or not running properly. Car thieves make more money by dismantling a car and selling the parts than by selling it in one piece.

  • Do not leave a driver's license, car registration, or other identification in the glove compartment of a car. Thieves have used these documents to sell a stolen car to an unsuspecting buyer.
  • Never have an identification tag with a name, address, or telephone number on the car key ring, since a lost key ring could lead a thief to the car.
  • Never keep an extra set of house keys in the car. If the car is stolen and the thief is able to obtain an address, the owner could become the victim of a home burglary.
  • Establish ground rules - instruct all family members on how to protect the car against theft.

Discourage the Thief

Avoid becoming the victim of a car hijacking. Park in a well-lighted and busy area, or in a well-lighted and attended garage, especially if planning to return to the car at night.

  • Lock all valuables in the trunk of the car or take them. A camera, handbag, package, etc. left lying on a seat is a temptation to steal.
  • Do not leave windows "cracked" for ventilation. Car thieves have tools that enable them to unlock cars through a minimum of open space.
  • Make it difficult for a professional thief to tow the car away. Park with the emergency brake on and the front wheels turned sharply to the left or right.

Lock It and Take the Key Away

An unlocked car is an open invitation to a car thief (four out of five cars were unlocked at the time of theft, and one out of five had the keys in the ignition). Close all windows, lock all doors, and take the key with you.

  • Do not hide an extra car key under the hood or another part of the car. Criminals know where to look for hidden keys.
  • When parking in a commercial lot or garage, leave only the ignition key with the attendant. Lock all valuables in the trunk and take the trunk key.

Use Identification Techniques

Engrave the vehicle identification number (VIN) on several hidden places of the car using an engraving tool (which can usually be borrowed from the local police). This will aid the police in identifying the car in the event it is stolen and later recovered.

  • Engrave the VIN on equipment and accessories.
  • Have the VIN etched onto the windshield and windows of the car to help in identification and to deter stealing the car for glass parts.
  • Place stickers on the car warning that all items have been marked for easy identification by the police.
  • Engrave the VIN under the hood and trunk lid.
  • Drop a business card down the window channel into the interior of the car door. This can help the police to identify the car in the event it becomes the victim of a "chop shop" (a place where component parts are stripped off a stolen vehicle).

Use Anti-Theft Devices

When buying a new car, check the dealer's list of security options.

  • Locks are available for various marketable parts of your car. Consider purchasing wheel/hubcap locks, battery locks, lockable entertainment system mounts, and gas tank cap locks.
  • Utilize a steering wheel locking device. These devices are bright in color, to make them noticeable, and hook onto the steering wheel, limiting its rotation.
  • On cars with the ignition switch on the steering column, utilize a steering column cuff or collar to protect the ignition switch.
  • Install a system interrupter, such as a starter disabler or an ignition cut-off or fuel cut-off device. These devices disable vital automotive functions, preventing the engine from being restarted until a hidden switch is activated. Other devices allow the car to run for a short period of time and then stall out, prompting the thief to abandon the car. Because of the risk that an ignition cut-off or fuel cut-off device could malfunction while the car is being driven, a starter disabler is usually recommended.
  • If the car is equipped with a vehicle alarm system, activate it when leaving the car. Sirens can scare off the car thief, especially the teenager looking for a joy ride.
  • Place a sticker or decal on the car indicating that it is protected by an alarm system. The decal may serve to deter a theft.

About Car Alarms

There are several vehicle alarm systems available that will serve to deter or discourage the car thief and alert others of forced entry into the car. These systems generally consist of detectors, a control module, and a sounding device. The detectors sense the intrusion and signal the control module, which activates the sounding device.


The intrusion detectors used in vehicle alarm systems include pin, tilt, and shaker switches; resonance and voltage sensors; and glass break detectors. Pin switches rely on plunger action, like traditional tamper switches, to open or close circuits, triggering an alarm. Tilt (or mercury) switches and shaker switches trigger an alarm when the vehicle is moved, such as being jacked up or lifted up for towing. Resonance sensors detect sounds of vandalism or intrusion, like metal-to-metal contact between a pry bar and the vehicle's door. Voltage sensors are wired into the electrical system of the car and trigger an alarm when a drain of power is detected, such as from an interior hood or trunk light. Glass break detectors discern the sound of breaking glass.

Control Module

At the heart of a vehicle alarm system is an electronic control module. The typical control module uses the car's electrical system for power, but can be provided with a backup battery to supply power to the alarm system should the car battery fail or be disabled by the thief.

  • In an active vehicle alarm system, the control module is turned on and off (armed and disarmed) manually through the use of a key switch or digital keypad or, on some systems, by simply tapping the brake pedal with one's foot. Newer systems can be controlled remotely by a key pad.
  • Passive vehicle alarm systems arm and disarm automatically at the turn of the ignition key or the locking or unlocking of the car. Passive systems are the preferred type because of their convenience in use.
  • Vehicle alarm systems generally have entry and exit delays, usually 10 to 15 seconds, to allow for time to get in and out of the car before the alarm goes off. Many have automatic cut-off features to silence the sounding device after a set period of time.

Sounding Device

Vehicle alarm systems are available that give the option of sounding an alarm locally, with a horn or siren, or remotely with a radio frequency (RF) paging system.

  • With a local system, to the extent that an alarm draws unwanted attention to a car thief at work, a louder alarm is better than a quieter one, and an alarm that sounds for a while is better than one that warbles briefly and then falls silent. The device should put out sound that can be heard up to 300 ft
  • (91.4 m) away. It should be noted that many municipalities have ordinances requiring that a vehicle alarm system be provided with the capability of automatically terminating the operation of the sounding device after a definite period of time, usually ten minutes.
  • Vehicle alarm systems, however, will not prevent the determined thief from stealing the car - they buy time and, perhaps, send the thief in search of an easier target. Vehicle alarm systems should be used in combination with the prevention measures discussed above.

Vehicle Tracking Systems

When all else fails, the final line of defense may be a vehicle tracking system, which can provide for emergency or distress aid, as well as help in the recovery of a stolen car. These systems depend on a radio transmitter hidden in the car that can communicate with a monitoring station to help locate it.

In one system, when a car is stolen, the owner reports the theft to the police and provides them with the car's identification number. The police then activate the hidden transmitter that, in turn, sends a coded signal to local patrol cars equipped with receiving equipment. Usually, the receiver in the police car can cover a 25-mi2 (64.7 km2) zone. A system disabler or vehicle alarm can be used in conjunction with the system. The major limitation of this system is that the car owner must report the theft before tracking can begin, and the police must be equipped to receive the signal.

Some vehicle recovery systems utilize global positioning systems (GPS) as the communication link between the car and a monitoring station. A transmitter in the car sends a signal to the satellite that relays it to the monitoring station, pinpointing the location of the car. This information can then be provided to local police. These systems can provide for emergency/distress signals, as well as allowing the monitoring station to disable the car.

Preventing automobile theft can turn your otherwise vulnerable car into a protected, and well-documented vehicle. Take on the task of accomplishing these goals at a pace that fits your schedule. The investment in time and materials will pay off in the long run, should your car ever fall victim to a robbery or theft. While you’re considering the various ways to protect your car, now’s a great time to review your auto policy and customize a policy that fits your specific needs. Contact your American Family Insurance agent (Opens in a new tab) today to discuss your options.

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