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What Is A Passive Alarm System On A Car

When it comes to securing our vehicles, there are various ways we can do this. Setting an alarm system is one of it. But even alarm systems are of different types. For the context of this post, we will be looking at the passive alarm systems. However, we might just be looking at other types too. So what is a passive alarm system on a car? We get that question sometimes, because the idea is to keep the car safe and secured at all times. So before you indulge in a passive alarm system, you need to understand what it is about.

What Is A Passive Alarm System On A Car

A passive alarm system on a car is an alarm system that will turn on automatically when the ignition has been turned off and the doors have been shut tight. When these happen, the passive alarm system kicks in. Once you have this alarm in your car, you rest easy, as you have to do absolutely nothing to turn it on.

This feature by itself is an advantage, in that you do not need to worry about turning the alarm on or off because it does this by itself. This guarantees a lot of car alarm protection since the car won’t have to depend on you to turn off or on the alarm system.

Passive car alarms make use of passive sensors that indicate abnormalities in around the system. For instance, if the car is locked and the alarm system notices there’s a sudden repeated movement on the lever of the car door, it triggers itself. It’s a very wonder type of alarm system to have in your car.


Having an alarm system that comes on and off by itself is very important as it is human nature to forget sometimes. Find below are some of the ways a passive alarm is important to a car owner.

Peace of mind

This goes without saying. Not when you have parked your car and traveled, you begin to worry about you activating and deactivating your car alarm system. Wherever you are, you are rest assured that your alarm system can take care of itself.

Lowers risk of hijacking

Not having a passive alarm system in your car makes it quite easy for the thief. Your car becomes highly vulnerable especially when it is parked in public places. But if you have a passive alarm system, this could even take the criminal unaware. Once he makes a move on the car, the alarm goes off and it creates a form of awareness to you or people around, who might now come to the rescue.


Decrease in insurance

The insurance premium you pay when you have a passive alarm system is usually lower as compared to other forms of alarm systems. This goes for both new and old vehicles. You are supposed to be the first person to secure your car before any company can do it for you.

So having a passive alarm system makes you pay less in event of any loss or damage. With an alarm installed, when the security and safety premium is being calculated you get to pay lesser because the risk factor for your vehicle is low.

Good second hand value

If the thought of selling your car ever comes to mind, know that having a passive alarm system in your car will help boost the resale value. People tend to pay higher for vehicles that have alarm systems pre-installed in them. It saves them the hassles of buying and installing one themselves as well as that extra security you feel when you know you can leave your car parked in public places without worry.


Among all the types of alarms to use in your car, a passive alarm is one of the best. The benefits you stand to get are more than what divers with other types of car alarms have. The first is that we are humans, and sometimes we forget things. And forgetting to turn on your alarm system can be detrimental, because you don’t know if there’s a plan to hijack the car at any time. I don’t think car hijackers give you prior notice.

I know we haven’t mentioned this, but having a passive alarm system requires that a chip be planted into the key of the vehicle. So once the key is used to lock the car, the chip automically communicates to the alarm system and it becomes active. Also, when the car is unlocked with the same key, the chip in the car key deactivates the passive alarm system.

Apart from being responsible for activating and deactivating alarm systems by itself, passive alarm systems will also disable the ignition of a vehicle, if someone tries to use a key that does not have the chip implanted in it. In fact, a higher level of passive alarm systems would lock the wheel and tires of the vehicle if there is a case of breaking and entering the car.


As excellent as a passive alarm system is, it has its own draw backs too. For instance, if the car’s intelligence system fails, this could cause the passive alarm to malfunction.

This could be a big issue because this malfunction could cause the passive alarm to activate and deactivate randomly. This will make the ignition hard to kick because the microchip will be activating and deactivating itself.

Another big challenge with the passive alarm system is that it is hard to turn off without using the car key that has its chip implanted into it. Let’s take for instance, a soccer ball slams into the wind shield of a car protected by a passive alarm system, deactivating it from the system button might not work.

The alarm will continue to sound until the key that has its chip is inserted into the ignition of the car. If the owner of the vehicle is not around, this could cause noise pollution, being a nuisance to the surrounding and even drain the battery of the car.


As earlier stated, there are numerous types of car alarm systems you can use for your car. The things that are challenges of the passive alarm system might be the merit of another type. It is also worthy of note that passive alarm systems can be used with other forms of alarm systems, and still function properly with its integration.

Some of the best alarm systems are as follows:

Active car alarms

As the name implies, this is the direct opposite of the passive type. For this type of alarm, you must turn on the alarm yourself. This gives the user total control of the alarm system. Once you lock the door for instance, the active alarm is activated consciously and the car is protected.

Car tracker

This is a very important type of alarm system to install in a vehicle. If a car is stolen for instance, it is easy to know the actual position of the vehicle if it has a tracker installed in it. Car tracker works with GPS. It has a lot of other functions this post is not designed to cover. However, just bear in mind that is a wonderful piece of equipment to have in the car.

Manual alarms

This type of alarm comes on when you press a button on a receiver. It can come in handy when you want to identify your vehicle quickly in a wide parking pool. By pressing the button, you can also activate and deactivate your alarm systems.

Manual alarms


The need for passive alarm systems in a vehicle cannot be over emphasized. That extra layer of protection it gives is very important, especially when it has the ability to turn off and on by itself without supervision.