The 10 Best Car Alarm Systems

The best car alarm system will help protect your car, truck, or SUV from theft.

Cars can be very expensive investments that most people can’t afford to have stolen. In addition to exercising good common sense when parking, arming your trusted ride with a quality alarm system is a great way to safeguard your vehicle against theft and vandalism.

Our detailed car alarm reviews and buying guide will help you find the best car alarm for your car, SUV, or truck. Here’s a quick rundown of our top picks.

Prices pulled from the Amazon Product Advertising API on:

Best Car Alarm System Reviews

It’s hard to go wrong with any of the car alarm systems we included in our list of favorites. With careful research, you might even be able to find another one that’s just as good, if not better, for your needs.

1. Compustar CS7900-AS All-in-One 2-Way Remote Start and Alarm Bundle

Our top pick is the Compustar’s CS7900-AS all-in-one car alarm bundle, a comprehensive suite of security-enhancing and convenience features that will likely not leave you wanting. It comes with a CM600 control module, a shock sensor, a loud siren, an LED indicator, and more.

This car alarm system can add shock sensors all around your vehicle to detect all manners of intrusions. And should there be an intrusion, a 2-way communication LCD remote will provide an up-to-date alert letting you know what’s going on.

As for convenience features, the system allows you to remotely start your car’s engine and control its HVAC system from up to 3,000 feet away, which should come in handy on particularly cold mornings or hot summer days.

The package also includes a backup 1-Way remote in case you misplace or lose the main remote.

There are few minor drawbacks worth mentioning. First, the alarm is very sensitive, so you may have to operate it at its lowest setting. Second, good technical knowledge is needed to install the system, making professional installation the recommended option for those who lack the skills.

Things We Like

  • Comprehensive suite of security and convenience features
  • Highly sensitive alarm
  • Long operational range
  • Remote engine start, HVAC controls

What We Don’t Like

  • Difficult to install

Bottom Line

The Compustar CS7900-AS is loaded with features and works exceptionally well to discourage thieves from stealing your vehicle. CHECK LATEST PRICE

2. Scytek A15 Keyless Entry Car Alarm Security System

The Scytek A15 may be the best budget car alarm system you can currently buy. For an incredibly low price, it is jam-packed with features.

Every must-have feature can be had with this unit, including keyless entry, smartphone compatibility, and an adjustable dual-zone impact sensor.

You also get a long list of security features such as engine starter interrupt, a user-programmable override switch, a special alert to scare away thieves, and GPS vehicle tracking, as well as convenience features such as priority unlocking, dome light supervision, and two-car operation using just one remote.

The various functions of the Scytek A15 are controlled via a one-way, five-button remote, though your phone can also be used as a controller, one with two-way communication. 

Finally, it’s easier to install than most other car alarm systems and can be upgraded to add even more features.

A noteworthy shortcoming of Scytek’s system is that it lacks a siren, relying instead on the car’s horn. Additionally, it can be a big drain on your battery if your vehicle isn’t driven regularly, and its operational range is a bit on the short side.

Things We Like

  • Features galore
  • Works with smartphones
  • Easy to install
  • Unprecedented value

What We Don’t Like

  • Doesn’t come with a siren
  • Operational range is limited

Bottom Line

The Scytek A15 Car Alarm Security System gives you all the essentials of a quality alarm system for an unbeatable price. CHECK LATEST PRICE

3. Avital 5305L Security System with 2-Way LCD Display Remote

Avital’s best car alarm system is another fully-loaded option that comes with all the security features you’d expect, including a dual-zone shock sensor; engine starter interrupt, a siren, and a two-way LCD remote.

It’s a very versatile keyless entry system that also allows you to control up to four different vehicles with just one remote and start the car from up to 1,500 feet away.

Speaking of the remote, its large LCD screen and two-way communication capabilities give you clear, up-to-date alerts and updates when the system is alarmed or disarmed, when the siren sounds, or when you issue other commands. A one-way remote comes as a spare.

The Avital 5305L is a great car security system, but its LCD remote is rather large and can be a bit confusing to use the first time around, especially if programmed to work with two or more different vehicles. Some users also found the instructions to be confusing and even insufficient. 

As with our number one pick, it’s highly recommended that you have the system installed by a trained professional.

Things We Like

  • Single remote can control several different vehicles
  • Remote engine start/stop
  • Large LCD for viewing command confirmations and notifications

What We Don’t Like

  • Complexity can make it intimidating to operate
  • Professional installation is recommended

Bottom Line

If you’re looking for a well-equipped alarm system with added convenience features, this security system from Avital is worth a serious look. CHECK LATEST PRICE

4. Viper 350 PLUS 3105V 1-Way Car Alarm Keyless Entry

The Viper 350 PLUS 3105V 1-Way Car Alarm won a spot on our list due to its straightforward, durable, and easy to install design, not to mention its reasonable price point.

It is a one-way, three-channel security system featuring a FailSafe starter kill, anti-carjacking mode, and a keyless entry remote with four buttons. Upgradable options include a GPS tracker and a remote starter, both of which which are sold separately.

This Viper unit also boasts an adjustable dual-zone shock sensor, a siren with six different tones, and a bright LED indicator light, features that lend to its versatility.  

Unfortunately, the siren isn’t exceptionally loud and may have to be paired with the car’s horn for increased efficacy.

Things We Like

  • Many mainstay security features
  • Trusted, reputable brand
  • Reasonable price

What We Don’t Like

  • Siren could be louder

Bottom Line

If you’re a budget-conscious buyer who wants a lot of bells and whistles without paying a premium price, the Viper 350 PLUS makes for a compelling buy. CHECK LATEST PRICE

5. Viper 5305V 2 Way LCD Vehicle Car Alarm Keyless Entry Remote Start System

While not the all-around best car alarm system from Viper, this unit is a great choice for those looking for a reasonably priced, well-equipped car alarm system from a reputable brand.

The 5305V is a two-way system with a 4-button LCD remote for controlling its various functions, which include keyless entry and an adjustable siren with six different tones.

Remote start, a dual-zone shock sensor, and smartphone compatibility are also part of the package, though additional components such as wiring harnesses and relays are required to get some of those functions.

The Viper 5305V features code-hopping technology that prevents thieves from replicating the key fob’s signal and overriding the system. Its quarter-mile operational range is decent but not great, however, and the key fob is a bit on the larger side.

Things We Like

  • Has many must-have features
  • Secure encryption
  • Trusted, reputable brand

What We Don’t Like

  • Key fob is bulky and easily scratched
  • Operational range may be less than advertised

Bottom Line

This mid-range Viper car security system comes with most of the security features you need to protect your car. CHECK LATEST PRICE

6. CARLOCK 2nd Gen Advanced Real Time 3G Car Tracker & Alert System

CarLock’s second-generation Advanced Real-Time 3G Car Tracker & Alert System is a high-tech yet extremely affordable alternative to typical car alarms. 

The system monitors your car and sends out alerts on your smartphone whenever it has been moved, its engine starts, and it sustains an unusual vibration or jolt.

It can even detect harsh acceleration, hard braking, and sharp cornering, alerting you whenever someone other than yourself (e.g. your teen) is driving the car recklessly, and keep a tab on the health of the vehicle to alert you of such issues as a low car battery, high battery drainage, and more.

A GPS component provides detailed trip tracking, letting you know where the car has been, whether someone stole it, or a “trusted” driver isn’t where he or she should be. 

This is a silent alarm system, meaning it doesn’t blast a loud siren alarm when an attempted theft occurs but rather alerts you privately of the incident. While this may make the thief unaware of your awareness, a loud siren can sometimes instill some fear and discourage the theft.

Potential downsides of CarLock’s unit are that it may not work as well as intended and depends on cloud computing and internet storage that require a monthly payment.

Things We Like

  • Monitors vehicle’s health
  • Comprehensive smartphone integration
  • Easy plug-and-play installation
  • Extremely affordable

What We Don’t Like

  • May not work as well as intended
  • Data storage requires monthly payments

Bottom Line

For such a small, easy to install, and incredibly affordable device, CarLock’s 2nd Gen Advanced Car Tracker & Alert System sure does pack a lot of functionality. CHECK LATEST PRICE

7. Crimestopper SP-502 2-Way LCD Paging Combo Alarm

The Crimestopper SP-502 is a solid budget pick that packs a lot of features for a reasonably low price. 

You get a siren and dual-stage shock sensor; remote start; a starter kill that prevents hot-wiring; smartphone connectivity; vehicle tracking; and a two-way remote with an LCD screen, real-time feedback, and a 3500-feet range. 

The car’s windows, climate controls, and trunk/hatch can also be controlled via your phone, while the remote is rechargeable, can be programmed to work on two different vehicles, and has both audible and vibration tones.

Even though the Crimestopper SP-502 is a bit complicated to install and its key fob feels a bit cheap, you will be hard-pressed to find a remote start, two-way communication car alarm system for a better price. 

Things We Like

  • Comes with a lot of features
  • Usable on two different vehicles
  • Long operational range Relatively low price

What We Don’t Like

  • Installation is complex
  • Cheap-feeling key fob

Bottom Line

Just about everything you want in a car alarm system can be had with the Crimestopper SP-502 at a reasonably low price. CHECK LATEST PRICE

8. Viper 5906V Color Remote Start & Security

This car security system is expensive, but that’s because it gives you everything you would want from a quality car alarm system without having to add upgrades like you have to with other systems.

It’s a two-way security system with remote start; a dual-stage shock sensor; a six-tone siren; a rechargeable, full-color OLED key fob; smartphone compatibility; and an impressive one-mile operational range.

There is also a failsafe starter kill, dome light supervision, and four auxiliary channels, and you can check your interior temperature and open the trunk using the remote, which can also be programmed to operate two different cars.

Possibly Viper’s best car alarm system, the  5906V has too many features to count — probably more than you need — largely explaining its premium price and why you’d be wise to have it installed by a trained professional if you have no experience with car alarms.

Things We Like

  • Most advanced car alarm system from Viper
  • Feature-rich, very versatile
  • Customizable OLED display

What We Don’t Like

  • Very expensive
  • Professional installation recommended

Bottom Line

The Viper 5906 is one of the most popular car alarm systems on the market because it’s one of the most comprehensive and sophisticated. CHECK LATEST PRICE

9. Python 5305P 2-Way LCD Security & Remote-Start System

Python is known for producing high-quality alarms, and the 5305P car alarm system is a particularly reliable and feature-rich option.

It comes with many security and convenience features, including shock sensors, remote start, a six-tone siren, and a GPS tracker.

The system can be operated and monitored using an app on your smartphone or tablet, while an LCD screen on its two-way remote provides live status updates on the vehicle.

While most of the wiring you need for installation is provided, we recommend that you have a professional set everything up for you. Installing a car alarm system can be very challenging for the inexperienced.

A few minor issues with the Python 5305P is that it has a bulky key fob and a rather short operating range.

Things We Like

  • Good security and convenience features
  • 6-tone siren
  • Easy-to-use smartphone controls

What We Don’t Like

  • Bulky key fob
  • Fairly limited range

Bottom Line

Minor issues aside, the Python 5305P is a well-rounded, easy-to-use car security system that will surely reduce the risk of a thief stealing your car. CHECK LATEST PRICE

10. Mengshen Wireless Anti-Theft Burglar Security Alarm

Mengshen Anti-Theft Alarm is the simplest product on our list as it’s mainly just a powerful alarm. However, it has several standout features that make it a compelling option.

For starters, the device can be used not only on cars, trucks, SUVs, and other types of motor vehicles but also on bicycles, motorcycles, scooters, mopeds, etc., making it incredibly versatile. And measuring just 64 mm by 45 mm, it is also very small and compact.

A waterproof shell allows the alarm to be used outdoors, while its 113db siren, which has 7 levels of adjustable sensitivity, is certainly loud enough to draw attention. 

Finally, installation is easy and can take less than 10 minutes. A remote control makes arming and disarming the alarm convenient and has a one-key find vehicle feature.

The Mengshen isn’t a top-tier security system because it lacks security and convenience features such as vehicle tracking and remote starting, but it can nevertheless act as an extra line of defense against potential thieves and vandals.

Things We Like

  • Extremely versatile, usable on bikes, motorcycles, cars, and other vehicle types
  • Easy installation
  • Very affordable

What We Don’t Like

  • Limited security features
  • No driver convenience features
  • Short remote range

Bottom Line

If you’re looking for an incredibly simple, affordable, and easy to install car alarm that can be used on virtually any type of vehicle, Mengshen has something for you. CHECK LATEST PRICE

Car Alarm System Buying Guide

Best Car Alarm System features displayed on Porsche Cayenne SUV

Car alarms are fairly inexpensive, easy to install, and have several other benefits that can make them a worthwhile investment. This guide provides important information that should help you find the best car alarm system for your car, truck, SUV, or RV. 

What Is A Car Alarm?

A car alarm is an electronic security device designed to discourage the theft of a vehicle and/or its contents. It’s installed in the vehicle and usually consists of one or more sensors connected to a high-volume sound device such as a siren, klaxon, or the vehicle’s horn.

Car alarms typically cause the vehicle to emit a loud prolonged sound once a sensor is triggered. The headlights may also flash and, with many modern systems, a notification of the incident will be sent to the owner via the key fob, a text message, or through other means.

Some sophisticated alarms are even programmed to interrupt parts of the car so that it doesn’t start.

Fun fact: In the U.S., over $6 billion was lost to car theft in 2019 alone. Fortunately, vehicle thefts have declined precipitously in the past 30 years due to advancements in anti-theft systems such as car alarms.

How Do Car Alarms Work?

Car alarms have come a long way since their widespread adoption in the 1970s and are more effective at discouraging theft than ever. Whereas early systems were simply a switch on the driver’s door that, if triggered, caused a siren to sound off, today’s alarms are much more sophisticated.

Modern car alarm systems typically consist of various sensors (switches, motion detectors, etc.), a loud sound system; a radio receiver that allows the system to be controlled wirelessly, and a computer unit that controls and monitors all the parts.

The way they work is simple: When a sensor is triggered, whether by a thief or accidentally, the computer turns on the sound system, emitting a loud prolonged sound that hopefully alerts the owner of the incident and scares away the would-be thief. 

You, the owner, can then use the car’s key fob, a smartphone, or another such device to remotely control the alarm, turning it off, locking and unlocking the doors, turning on the exterior lights, or even immobilizing the car’s engine.

The car alarm remains active even when no unusual activity is detected but in a silent and unnoticeable mode.

Car Immobilizer vs Car Alarm

Car alarms and car immobilizers are often seen as the same thing. While they serve the same basic function — that is, prevent your vehicle or its contents from being stolen — they operate in entirely different ways.

A car alarm informs the car owner of a potential theft attempt by emitting a loud sound or signaling with other conspicuous means. An immobilizer, on the other hand, doesn’t produce a noticeable alert of any kind but instead prevents the engine from being turned on so that the thief can’t drive off with the car.

Car immobilizers, therefore, literally immobilize your vehicle, making it unable to run until you use a transporter chip to unlock the engine. This makes them more effective at preventing theft than car alarm systems, seeing as regular alarms can’t stop someone from hot-wiring the car and driving it away.

But as effective as car immobilizers are, they can’t prevent thieves from towing your car away, an act that can often be detected by the shock sensors used by the top car alarm systems.

Granted insurance companies prefer car immobilizers over car alarms, these electronic security devices complement each other so well that installing both is often the best way to keep your vehicle safe.

Benefits Of Car Alarm Systems

After a home, buying a car is the biggest investment most people will make in their lifetime. The high value of your vehicle makes it a prime target for theft, so investing in a quality car security system can be invaluable. 

Let’s look at the key benefits of installing a car alarm system.

Protect Your Car

Thieves always go after the vehicles they think are easy to steal and are less likely to target ones that are clearly protected. Although car alarms are very simple devices, they send out a clear message to them that there is a high chance of someone being alerted of their actions.

A quality car alarm system will provide some level of protection for your vehicle and its contents. To provide your belongings with even more protection, consider concealing them by also tinting your windows and using car sun shades.

Lower Insurance Premiums

Insurance is one of the biggest costs of owning a car, and not having an anti-theft system such as a car alarm installed only makes it higher.

An increasing number of new cars have anti-theft features that insurance companies consider when calculating monthly insurance premiums. If you have an older car that lacks such security features, you may be able to lower your insurance by installing one.

Car alarms, in particular, are so affordable that the cost of buying and installing one is often offset by the amount saved on insurance alone.

Recover Your Stolen Car

Many modern car alarm systems have a built-in tracking feature that transmits the location of the vehicle in the event it is stolen, with the thief being none the wiser. 

This will allow the alarm company and law enforcement to track, locate, and retrieve the vehicle a lot more quickly than if it wasn’t equipped with a GPS tracking system. 

Considering that a vehicle can be disassembled for parts resale in just five hours after being stolen, recovery speed is of the utmost importance.

Additional High-End Perks

Some advanced car alarm systems incorporate many convenience features such as keyless entry, customizable alarm tones and volume, and a parked car locator. 

Some even have remote engine start/stop capabilities, which can be used to stop your car from moving should you catch a thief trying to make off with it.

Types of Car Alarms

All car alarm systems are designed to prevent the theft of your vehicle or its contents, but not all of them work the same way. There are several different types of car alarms, and we discuss them in this section.

Active vs. Passive

Car alarm systems can differ in whether they are passive or active. With passive alarms, the system automatically activates whenever you turn off the engine of your car and lock its doors and deactivates when you unlock the doors.

This type of car alarm is primarily intended for forgetful drivers or those who simply prefer a less engaging approach to securing their vehicle.

Active car alarm systems, on the other hand, are activated manually, usually at the push of a button. Unlike a passive alarm, simply turning off the engine and locking the doors will not arm the system and protect your vehicle from theft.

If you are someone who prefers a more engaging experience for securing your vehicle, this is the type of alarm to get.

Audible vs Silent

A distinction can also be made between alarms that make a sound and those that don’t.

As you likely guessed, audible car alarm systems emit a loud alert whenever a sensor is triggered. The audible alert can range from the car’s horn honking repeatedly to a more distinctive, attention-grabbing alarm tone. 

The idea with these systems is to draw attention to the mischievous individual in hopes of discouraging him or her from vandalizing or breaking into your vehicle. However, they can be very annoying to the general public, especially when accidentally triggered and not turned off promptly.

Silent car alarm systems don’t make a noise and instead only digitally notify the owner of a potential break-in. Since there is no audible cue warning the thief of the alarm going off, you get a good opportunity to catch him or her in the act. 

Of course, you should always contact law enforcement of a potential break-in before confronting the culprit. Some silent car alarms can even be configured to automatically inform the police of the act.

One Way vs Two-Way Communication

Finally, car alarm systems can be grouped according to how the vehicle and the driver communicate. Some alarms do nothing but only allow the driver to arm or disarm the system, while others are able to communicate back to the driver.

The latter type provides two-way communication and lets you know what’s actually going on with your vehicle. 

Not only do they allow you to activate or deactivate them, but they also alert you when the system has been engaged or disengaged, the doors are locked/unlocked, and the alarm is triggered. 

Two-way communication is an advanced feature typically found on premium car alarm systems.

Top Car Alarm Brands

The car alarm segment is dominated by a few brands: Avital, Compustar, Viper, and Python.


Avital Auto Security Systems is owned by Directed Electronics, one of the world’s largest global security companies. As a trusted brand, it offers consumers a wide range of technologically sophisticated, highly effective, and easy-to-use security systems that are relatively affordable. 

The Avital 5305L is a very popular car alarm system.


Compustar is the flagship brand of Firstech, an award-winning producer of automotive electronics. Manufacturing car security and remote start systems for over 20 years has made it a highly regarded brand.

The Compustar CS7900-AS is easily one of the best car security systems.


Like Avital, Viper is owned by Directed Electronics. Decades of experience have made it one of the world’s most reputable and best-selling vehicle alarm and security brands.

Viper’s product lineup includes remote start security systems and smartphone alarms for cars, with one of their best-sellers being the Viper 5906V Color Remote Start & Security.


Python is another member of the Directed Electronics family, along with Avital and Viper, and is one of the biggest names in the vehicle alarm and security world.

Its products, such as the Python 5305P 2-Way LCD Security & Remote-Start System, generally fall in the premium category, so you can almost always expect them to feature the latest in cutting-edge technology.

Features Of The Best Car Alarm System

The basic alarm systems that most modern cars come with are often too bare-bones to deter experienced car thieves. To effectively safeguard your vehicle, you need a robust alarm system that boasts a range of bells and whistles.

Here are the essential features you should look for when shopping for a car alarm.


Go with a car alarm system that, at the very minimum, makes some noise when one or more of its sensors are triggered. 

You also want one that has shock sensors, which will detect when your vehicle is jolted by an impact such as when it’s hit by something, one of its glass gets smashed, or a would-be thief tries to tow it away.

If the car alarm system features a siren or is hooked to your car’s horn, an audible alarm will be tripped when any of those incidents occur. If it has mobile alerts, you will be notified of the occurrence.


You want to be able to engage with your car alarm system from as far as possible, so look for one that has a range of at least 1,000 feet. 

Having long range will help ensure your alarm is always set every time you walk away from your vehicle.

Carjack Protection

Think of carjack protection as a collection of active preventative measures that work concurrently to deter thieves from taking off with your car. These typically include loud sirens, chirping alarms, flashing lights, and kill switches.

While it may seem redundant to have all these security measures operate at the same time, research has shown such a setup to be effective at deterring thieves.

Not all car alarm systems come with carjack protection, so check to make sure the one you are considering has the feature.

Two-Way Remotes

Basic car alarms typically feature one-way communication, which only allows you to arm or disarm the alarm and lock or unlock the vehicle’s door using the key fob, a smartphone, or another control unit. What you want is a system that is also able to communicate back to you.

Two-way alarm systems send you feedback regarding your commands, giving you a better idea of what’s going on with your vehicle. Some premium models even have an LCD screen that displays your inputs and the alarm’s security alerts.

Encrypted Transmission

A crowbar or Slim Jim isn’t the go-to tool for all thieves. Some tech-savvy individuals take the digital route, hacking the signal transmitted from your key fob or smartphone and remotely unlocking your vehicle.

If you are intent on having a car alarm system with remote entry, make sure it has an encrypted transmission that makes hacking difficult. Well-designed and packaged car alarm systems usually do.

Mobile App Integration

An increasing number of car alarm systems work seamlessly with mobile apps to allow you to monitor, control, and manage your vehicle’s security from the comfort of your smartphone. 

They also make two-way communication more convenient, making it easier to receive alerts via texts and emails.

Don’t want to trouble yourself with an extra fob or remote? Smartphone integration will free you from carrying one.

Ease Of Installation

Installing a car alarm involves tinkering with so many wires and the car’s sophisticated electrical system that it’s often advised to have a professional do it. However, going with a professional can be very expensive.

Fortunately, as many car owners have demonstrated, it’s quite possible to install one yourself. Going with a car alarm system with a straightforward installation process and following the manufacturer’s instructions will make the task easier.

Beware, however, that DIY installation can impact any warranty the equipment has if performed carelessly.

Convenience Features

Some high-end car alarm systems have added convenience features that allow you to control other functions of your vehicle, features such as keyless entry, remote start, trunk release, and even valet mode.

If your car is lacking in convenience features, getting a car security system that comes bundled with them will certainly make your life easier.

How To Install Car Alarms 

Best Car Alarm System - man conducting installation

Car alarm systems can be difficult to install since they require tinkering with your car’s intricate electrical system and dealing with many wires, so consider getting professional help if you lack the time and skills to confidently carry out the task.

If you’re so inclined to do it yourself, make sure to follow the instructions provided by your car alarm manufacturer. You can use the following step-by-step guide as a general guideline for installing one.

Tools You Need

Installing a car requires several key tools. On top of obtaining the best car alarm system for your vehicle, you will need the following equipment.

  • Multimeter
  • Electric tape
  • Handheld Drill
  • Soldering Iron or Crimping Tool
  • Wire strippers/cutters
  • Zip ties
  • Mechanic gloves

Note: Always check the user manual of your chosen alarm system for any additional tools you might need for installation.

Installing The Car Alarm

It’s worth pointing out that the more features a car alarm system has, the more work the installation will require. If you have a feature-laden car alarm, having it professionally installed would be our recommendation.

To keep things simple, this guide mainly focuses on setting up a car alarm’s main control unit, siren, and shock sensor, and nothing else. It is only a general overview.

1. Install The Main Unit

Check your user manual for where in your car the alarm’s main controlling unit (brain) should reside. Most need to be wired into the car’s ECU to interact with door and window sensors and planted inside the dashboard, usually under the steering wheel column or behind the glove compartment.

Remove the panel covering the dashboard area and wire the harness that came with the arm to the ECU. 

2. Install Additional Sensors

If your system came with additional sensors such as a shock sensor, install them as well.

Shock sensors are normally positioned behind the panel covering the driver’s side door frame. Remove a small enough part of the panel so that you can run the sensor’s wire to the alarm system’s main unit. 

Running the wire from the front edge of the driver’s door and under the floor carpet will make it less conspicuous. 

3. Install Indicator Light

Your alarm likely came with an indicator to signal whenever the system is active. It’s usually a small LED light that must be mounted somewhere in the dash. 

Place it at a location where it can be easily seen, and wire it to the rest of the system. You might have to drill a hole in the dash to secure it in place.

4. Install The Siren 

The first thing you need to do is find a metal surface to mount the siren onto. Most are designed to be placed in the engine bay unobstructedly. 

Don’t place the siren near hot engine components such as the exhaust manifold and any turbochargers that might be present, and face it downwards so that water doesn’t easily enter it.

We recommend installing it on the firewall, which separates the engine bay from the vehicle’s interior. 

The siren’s wires need to be passed through the firewall and connected to the control unit, preferably via a pre-existing hole. While it’s possible to drill a hole into a rubber or plastic section of the firewall, only do so as a last resort.

5.Test The Alarm System

After all the parts are connected and the entire car alarm system is installed, you want to test it out to make sure everything works as intended. The first way to do this is by pressing buttons on your key fob or smartphone to try out each function.

You can also try tripping the alarm by jostling one of the doors.

6. Bundle And Secure The Wires

If the system works as intended after being tested, you will want to bundle any loose wires to protect the connections and keep things tidy. This can be done using zip ties, electrical tape, and/or a heat shrink wrap.

Next, secure the bundle inside the dashboard so that it doesn’t get jostled around as you drive, possibly setting off the alarm.

Car Alarm System FAQs

Best Car Alarm System being operated from smartphone

In this section, we answer some of the most common questions about car alarm systems to address the misconceptions people have about them.

Do Car Alarms Work To Prevent Auto Theft?

While car alarms can reduce the risk of theft, experienced thieves are usually not deterred by a sounding alarm. 

That’s because people nowadays presume most tripped alarms to be accidental and ignore them as a result. Also, thieves have developed advanced theft methods that allow them to quickly steal a car before the owner can do anything.

Fortunately, the best vehicle alarms often come with other anti-theft features that make it much more difficult for thieves to steal your vehicle, features such as shock sensors, engine immobilizers, and encrypted transmissions. 

Do I Need An Aftermarket Car Alarm If My Car Has An Anti-Theft System?

Yes, you may need one. Not unless your pre-installed alarm system is advanced, it will likely not be sufficient enough to ward off thieves. 

Most factory security systems only consist of a simple noise-maker and door switch sensor and possibly an engine immobilizer. 

While immobilizers can be effective, professional car thieves can easily work around them. What you need is a car security system that also incorporates a shock sensor, encrypted transmission, and a very audible siren that easily draws attention to the would-be thief.

Is It Difficult To Install A Car Alarm System?

Compared to other car accessories, it can be very challenging to install an aftermarket car alarm system as you will have to play with your car’s wires and electrical system.

Those who have the technical expertise, tools, and time should be able to handle the job confidently. For those that lack the necessary experience, we recommend having a professional install the alarm system.

Will Installing An Aftermarket Car Alarm Void My Vehicle Warranty?

No. If you are in the United States or Canada, the Magnuson-Moss Warranty Improvement Act and Consumer Protection Act, respectively, allow you to install aftermarket parts that improve a vehicle’s performance without voiding your warranty. That includes car security systems.

That being said, if you butcher the installation by haphazardly cutting wires and making holes in places where there shouldn’t be any, you may compromise your warranty. If this concerns you, consider having your alarm system installed by a professional. 

Will A Car Alarm Drain My Car Battery?

Yes. Car alarm systems require energy from your battery to operate, though the rate of drainage will depend on how well the alarm system is installed and how many systems of your car (lights, horn, etc.) it connects to.

If installed properly, a well-designed car alarm system won’t place excessive strain on your car battery.

Final Thoughts

If you’re like most people, you spent a lot of money on your car, so much money that you probably can’t afford to have it stolen. Fortunately, equipping it with a quality car alarm system can reduce the risk of a thief driving off with it.

We reviewed and ranked some of the best car alarms on the market and put together a detailed buying guide to help you weed through the myriad of options available and find one that will provide solid protection for your vehicle.

If you were to ask us, the best car alarm system is the Compustar CS7900-AS All-in-One Remote Start and Alarm Bundle as it comes with an extensive list of features for safeguarding your vehicle and its contents, including shock sensors, two-way paging, and shock sensors, not to mention great battery life.