With car theft being a major concern for drivers, car alarms are often touted as an effective anti-theft device. But do audible alarms really stop a determined thief? Let’s examine whether modern car alarms are fulfilling their main purpose of deterring would-be car thieves.
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What are car alarms?
A car alarm is an electronic device installed in vehicles that emits a loud sound when it detects a threat such as forced entry into the car. The alarm is designed to attract attention in order to deter potential thieves from stealing the car or its contents.
Modern car alarms are controlled through a central module that monitors different kinds of sensors installed in various parts of the vehicle. Some of the common sensors that can trigger a car alarm include:
- Door sensors – Detect when a door is opened.
- Trunk sensors – Detect when the trunk is opened.
- Shock sensors – Detect impacts to the body of the car.
- Tilt sensors – Detect change in the car’s tilt angle, such as when it’s being towed.
- Ignition sensors – Detect when someone tries to start the car’s engine.
- Motion sensors – Detect movement inside the car.
- Glass breakage sensors – Detect the sound frequency of shattering glass.
When any of the sensors are tripped, the car alarm’s brain module activates the deterrents – usually a siren, vehicle horn, flashing lights, or a combination. This cacophony is intended to scare away the would-be thief and attract attention before they can steal the car or its contents.
Brief history of car alarms
While car alarms have been around for decades, modern alarm systems became popular in the 1980s and 1990s. As auto theft rates in the United States hit historic highs during this period, consumers began demanding better anti-theft protection.
The early car alarms were simplistic devices focused solely on perimeter protection. These first-generation alarms used vibration sensors or switches on entry points like doors and trunk lids. When activated, they would make a loud noise to scare away intruders.
However, thieves soon learned to disable these simple alarms by entering the car forcefully in a way that prevented the sensors from detecting entry. This led to the development of more sophisticated alarm systems with multiple redundant sensors to protect all areas of the car.
Modern car alarms emerged in the 1990s with the incorporation of microprocessors that could monitor multiple sensors and activate deterrent devices in a configurable sequence. These computerized car alarms provided perimeter as well as interior protection.
Over the last two decades, car alarm capabilities have continued to evolve with new sensor technologies and integrating with other car systems like ignition immobilizers. However, the basic purpose remains deterring opportunistic theft through loud noise activation.
Do car alarms actually prevent theft?
Despite the ubiquity of car alarms, it’s debatable whether they actually deter or prevent many car thefts. Critics point to several factors that limit the effectiveness of car alarms:
Nuisance alarms are often ignored
Car alarms get triggered so frequently by benign causes like weather events or animals brushing against the car that people tend to ignore them. According to estimates, over 90% of car alarm activations are false alarms rather than actual theft attempts.
When car alarms are crying wolf on a daily basis in public areas, most passersby simply tune them out. This “noise pollution” means that real theft attempts often don’t garner any special attention.
Sophisticated thieves know how to disable alarms
While car alarms may thwart opportunistic amateurs, professional car thieves usually know how to circumvent them. Common techniques include:
- Disconnecting the car battery or cutting power cables
- Using RF jamming devices to block alarm signals
- Entering through windows to avoid door/shock sensors
- Using “jiggle” tools to manipulate locks and latches
- Switching off alarm fuse or computer module
With proper tools and expertise, alarms can be neutralized within seconds. And professionals usually prepare by scoping out car alarm systems ahead of time.
Most thefts occur when the owner isn’t around
A major limitation of car alarms is that they are only a deterrent when the owner or other witnesses are within earshot. But research shows over 70% of car thefts occur when the owner is not around to hear the alarm.
Professional thieves boost cars from parking lots, driveways and curbsides when they know no one will intervene. The alarm alone does nothing if the owner is at work, asleep at home, or even just inside a store.
Quick theft of valuables
While it’s relatively difficult to steal an entire car, thieves can still quickly smash windows and grab valuables from the cabin before an alarm draws attention. Radios, cellphones, laptops, bags and other readily removable items are prime targets.
With peak alarm noise taking 3-5 seconds after glass breakage, thieves have enough time to grab exposed goods in plain view even if the alarm eventually sounds.
Recovery rates are still low
The ultimate proof of effectiveness for an anti-theft device is recovering stolen vehicles. However, recovery rates for stolen cars have not shown significant improvements despite the prevalence of alarms.
Just over 50% of stolen vehicles are recovered, typically when the stripped carcass is dumped haphazardly. For pros who can disable alarms, the chance of finding an intact stolen car before it’s chopped for parts or shipped overseas remains low.
Are alarms completely useless?
While the deterrent effect may be overstated, it’s incorrect to say car alarms are completely useless:
- Serves as a mild deterrent against casual theft – While pros aren’t deterred, amateurs may think twice.
- Protects against grab-and-run theft – Can thwart casual smashes of windows to grab valuables.
- Sense of security for owners – Provides peace of mind even if effectiveness is limited.
- Multiple layers of security – When used with locks, immobilizers etc., alarms add another layer of protection.
- Cheaper than more secure systems – Alarms have low hardware costs compared to CCTVs, tracking etc.
For ordinary drivers concerned about opportunistic break-ins and grab-and-run thefts, a car alarm adds a measure of protective value. However, high-end vehicle owners have less incentive to rely on basic alarms alone for securing cars from determined thieves.
Are smart alarms and new tech more effective?
Modern car alarms are getting increasingly “smarter” and connected, which could enhance their theft deterrence:
Smartphone linking and notifications
Newer alarms can link to a smartphone app, letting you monitor status from afar and get instant notifications if the alarm is triggered. This means you don’t need to be within earshot to know your car is under attack.
Remote cutoff capabilities
Some advanced alarms offer remote “cut off” capability where you can silence the alarm and even disable the thief’s ability to start the car through your app. This feature has greater impact when the owner can intervene remotely.
Onboard tracking devices
GPS trackers integrated with alarms provide vehicle location tracking that can aid recovery if a thief makes off with the car.
CCTV Integration
Linking the alarm to CCTV cameras on and around the vehicle provides visual verification of any criminal activity. It may also capture identifying images of the thieves.
Sensor advancements
OEMs are incorporating more sophisticated alarm sensors like dual-stage shock sensors, tilt sensors, interior temperature monitors and battery voltage readers to get earlier warning on theft attempts.
Immobilizer integration
The most sophisticated alarms are integrated with immobilizer systems, which can prevent the car from starting or being driven when the alarm is activated. This can foil thieves even if they manage to disable the alarm siren.
While these features help improve effectiveness, sophisticated thieves may still find ways to defeat modern smart alarms. And these systems add to costs, making them unavailable to many mainstream vehicle owners. However, tech advances do offer hope of reducing traditional car alarm limitations when implemented properly.
Are car alarms worth getting?
So should you pay extra for installing a car alarm or upgrade to a smarter alarm system?
Here are some guidelines for deciding whether getting a car alarm is worthwhile:
- High-theft risk area – More benefit in urban areas with high rates of car theft.
- New or luxury vehicles – Prime targets, so alarm is a must.
- Older cars – Probably not cost-effective due to lower theft risk.
- DIY installation – Has lower cost than pro installation.
- Consider immobilizer – An immobilizing system may be better alternative.
- Parking locations – Alarms have less impact if parking in isolated areas at night.
- Usage habits – Low benefit if rarely park on street or leave valuables inside.
- Smart alarm capabilities – Consider new features like phone linking, tracking etc.
Based on these factors, a car alarm may provide only limited protection from theft. But it offers more benefits in higher theft risk situations. And smarter connected alarms are showing promise of overcoming traditional limitations when implemented effectively.
Conclusion
While audible car alarms do serve as deterrents against casual theft attempts, experienced car thieves have long learned to bypass these rudimentary systems. With the proliferation of false alarms also numbing people to the noise, conventional car alarms provide minimal protection on their own given current realities.
However, modern smart alarms integrated with immobilizers, CCTV systems and tracking devices help counter traditional shortcomings. When supplemented with proper usage habits like parking in well-lit areas and not leaving valuables inside, an alarm system still adds a layer of car protection that has value for the right vehicle owners.
In summary, a standard car alarm alone is no guarantee against auto theft despite the noise it promises to make. But when appropriately implemented as part of a robust multi-layered security strategy, today’s more advanced connected car alarm systems still offer a meaningful deterrent capability.