What You Need to Know to Find Your Best Car Alarm

There are a number of situations where car alarms can definitely come in handy, but finding the best car alarm for any given situation can seem pretty complicated. You can’t always test drive a car security system like you can other aspects of a vehicle, but familiarizing yourself with some basic information will help a lot.

If you have a lot of expensive equipment in your car, or you live in a high crime area, then an alarm can help protect your investment and give you some much-needed peace of mind. Basic car alarms can be quite affordable, and even fancier systems with all the bells and whistles typically represent a smaller investment than replacing an expensive aftermarket sound system.

While even the best car alarm in the world can’t stop all thefts, outfitting your vehicle with an alarm will make it a less appealing target for many thieves.

There are four main factors that can help you settle on the best car alarm for your vehicle. Some of these factors are more important than others, but it’s important to take them into account. Before you buy a car alarm, the most important factors to consider include:


The best car alarms come with a variety of sensors that are able to detect an in-progress theft via a variety of means.


The other main component that a good car alarm needs to include is a noise-making device, like a loud siren, that goes off when someone attempts to steal the vehicle.


Good documentation, either in the package, or online, is absolutely vital if you’re planning on buying and installing your own car alarm.

Modular options

You can buy a car alarm, install it, and be done, but the best car alarms are modular, meaning you can pick and choose the features you need, and either install them all at once or go back and add things you want later on.

Since car security systems depend on a variety of sensors to detect the presence of a thief, this is the most vital factor to consider. Basic car alarms just come with door sensors, but more expensive systems can be much more complex. Some of the most common sensors include:

  • Door sensorsActivate the alarm when a thief attempts to open the door.
  • Movement sensorsActivate the alarm when the vehicle is bumped or jiggled.
  • Broken window detectorsActivate the alarm when a window is broken with a microphone that detects breaking glass, or a pressure sensor to detect the change in pressure resulting from the window breaking.
  • Motion sensorsActivate the alarm or sound an audible warning when motion is detected near the vehicle.

If you’re working on a tight budget, a basic alarm that only has door sensors is better than nothing. However, it is very easy for thieves to bypass these systems by just breaking a window. If you want to prevent that, you’ll need a system that includes a microphone or pressure sensor. Movement sensors can also be helpful since they will trigger the alarm if a thief rocks the vehicle back and forth or from side to side.

Motion sensors are useful if you have a convertible since they allow you to leave the top down. However, these sensors are difficult to calibrate properly, and any movement in or near the vehicle will cause the alarm to go off. That means a stiff wind and some leaves or a pair of fuzzy dice hanging from the mirror will often trigger a false positive, which won’t make you very popular with the neighbors.

You Have to Make Some Noise

After you’ve decided on the sensors you need, you can start thinking about the siren. The primary purpose of the siren is to draw attention to your vehicle, which may cause the would-be thief to abandon it in favor of easier targets. However, the siren itself may also deter the thief from entering your vehicle or driving away in it.

Some sirens are designed to be mounted inside the vehicle cabin, in which case they can generate a level of sound that is actually painful to the would-be thief.

Diy Car Alarm Installation Vs. Hiring a Professional

Installing a car alarm isn’t exactly rocket science, but the difficulty is often compounded by poor documentation. If you intend to save some money with a DIY installation, then it’s vital to look at the available documentation before you make a purchase. Many inexpensive car alarms work just fine once they’re installed, but they may come with poor documentation. And if you can’t tell which wires to cut or splice into, your money-saving DIY installation can turn into a headache real fast.

Some car alarms come with excellent documentation, and certain retailers even provide end-user support to help you through the DIY process. If you don’t have access to detailed wiring diagrams for your vehicle, and you haven’t installed a car alarm before, that kind of support is indispensable.

Future-proofing and Additional Features

If you’re looking beyond the basics, there are a number of useful features that can be integrated into a car alarm. Some of the features you might look for include:

  • Key fob or app control
    Most car alarms come with a key fob that allows you to activate and deactivate the system, but some of the best car alarms out there also include features like app control.
  • Remote startOne of the most useful additional car alarm features you can find, a remote car starter allows you to safely warm your car up without ever unlocking the doors or even leaving your house.
  • Door lock controlIf your car didn’t come with automatic door locks, you can sometimes add them as part of a security system. Some systems can also tie into existing automatic locks if you don’t already have a remote.
  • Driver’s door priority unlockPriority unlock allows you to remotely unlock just the driver’s door while leaving the rest of the doors securely locked.
  • Window controlsSome car alarm security systems can tie into your power windows, allowing you to operate them remotely as well.

Even if you’re only looking for a basic alarm right now, buying a system that has one or more remote outputs can allow you to turn it into the best car alarm around in the future. That will let you add bells and whistles to your bare bones security system as time and budget allow.