For many of us, a personal vehicle is one of our most prized possessions, but it's unfortunately also one of the most vulnerable when it comes to theft. One solution to this problem is a quality after-market car alarm system.
These systems can provide an extra level of security, including the ability to shut down or start an engine remotely. Advanced two-way systems are designed to communicate with an app or other device to alert owners of any possible tampering.
If you are in the market for an after-market car alarm system, read our helpful shopping guide for more information. Our top pick is the Viper 3400V Three-Channel One-Way Car Alarm System, which is an advanced three-channel model that includes both a panic button and an engine starter and immobilizer.
There are essentially two different methods for activating a car alarm system. An active system automatically sets the alarm after the driver closes and locks the door. The advantage to active activation is that the driver cannot forget to set it. However, the driver must be sure to deactivate the alarm before re-entering the vehicle or risk triggering the alarm accidentally.
Higher-end car alarm systems may offer a passive alarm option, which means the driver can activate or deactivate the alarm remotely through a special fob or app. Passive alarms are easier for drivers to control, but they can also be more expensive to install.
One-way or two-way communication
Many entry-level and midrange car alarm systems offer one-way communication only. In these systems, the driver can use a remote key fob or app to set the alarm or disable the engine or unlock a door, but the alarm itself does not provide status information back to the remote or app.
A more advanced two-way communication system allows the alarm base and the transmitter to share information in real time. If a sensor is triggered, the owner receives an immediate alert from the alarm unit. The driver can choose to reset the system remotely, return to the vehicle, or even disable the engine and contact law enforcement.
Older car alarm systems often used shock and vibration sensors, which meant a higher-than-average number of false alarms triggered by thunder or other loud noises. Modern systems still use these types of sensors, but they can now be calibrated to reduce their level of sensitivity. Some systems may also have contact sensors on doors, trunks and windows. A sensor mounted on the engine can also detect, and in some cases disable, any unauthorized engine starts.
Car alarm systems are great defenders of an unattended car, but sometimes the danger is to the driver as well as the vehicle. If a driver feels threatened, some systems allow him or her to hit a panic button on the remote control. This feature will lock the doors and activate attention-getting lights and sirens. The alarm system can be cleared after the driver receives assistance or feels safe enough to drive away from the area.
There are times when a driver needs to hand over control of the vehicle to authorized users, such as valet parkers, auto mechanics, or sales agents. Some car alarm systems will temporarily disable the sensors until the original owner reactivates them.
Sophisticated car thieves can actually duplicate the most common security codes used by car alarm system manufacturers. One popular solution to this issue is a system that changes the security code at random. Only the holder of an authorized remote can communicate with the alarm system, and that information is not available to hackers.
An entry-level car alarm system, essentially a single sensor and siren, can be found for $25 to $35, while mid-range models with basic features run between $40 and $75. For advanced features such as two-way communication and smartphone connectivity, retail prices (including professional installation) can reach $250 or more.
Q. Will an activated car alarm system drain my battery?
A. Most car alarm systems draw very little power from the battery while in stand-by mode. If your battery and alternator are in good working condition, a car alarm system should provide constant service for several weeks on a single charge.
Q. Does installing an after-market car alarm system automatically void my car's original warranty?
Our take: While professional installation may be required, this higher-end two-way system has a remote start function and multiple alert options.
What we like: Easy to install on older vehicles. Two-way signal sends tampering alert up to a mile away. Transmits multiple alarms, including text, tone, and vibration.
What we dislike: Remote control can lose power and range unexpectedly. Some reports of a missing instruction manual.
Michael Pollick is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money. BestReviews never accepts free products from manufacturers and purchases every product it reviews with its own funds.
BestReviews spends thousands of hours researching, analyzing and testing products to recommend the best picks for most consumers. BestReviews and its newspaper partners may earn a commission if you purchase a product through one of our links.