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Why does my car alarm keep going off?

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  • 5 min read

If you have been getting disturbed by the blaring security alarm of your car constantly at either odd times or specifically at night, then you might be both worried and irritated. While there can be a number of reasons other than your common intruder, a loud car alarm can be noisy and disturb other people living in the area which can lead to complaints.

In this article, we will be dealing with all the possible causes that might be causing the alarm on your car to go off.

Also read: Android Auto keeps disconnecting: Quick Fix

Reasons behind the blaring noise

There can be many reasons why your car alarm seems to be going off regularly and finding out the right cause can help you solve the issue as soon as possible. Some of the reasons why your car alarm may be going off are given as follows:

Low battery

Every feature in your car requires an optimum amount of charge from the car battery to function. If your car’s battery is low, then the car alarm system will not receive enough voltage and will end up being set off. If your car battery seems low or dead in the morning after the alarm went off at night, then it can be a clear indication that your car battery is low.

The car alarm is one of the ways that warns the driver about a low car battery. You can take care of this by checking the voltage reading of your car ad you can shut off the alarm by switching on your car once. The next day you can take your car repair shop for the battery to be replaced or charged.

Defective sensors

Your car has many sensors for the bonnet, boot, and door and if they malfunction then it can cause the car alarm to go off. These sensors also go off if someone tries to forcefully break into your car. The different types of sensors make the car alarm go off due to the following reasons:

  • Door sensor: This sensor is located inside the door lock actuator. It has an open and closed wire system which can be affected during rain when water seeps into the door. To avoid any breakage, you can seal the wires and connector with grease as well as take care of all water leaks. Make sure that all door lock connectors and actuators are up to the mark to avoid dealing with a defective sensor.
  • Bonnet sensor: The bonnet also has a sensor in the latch that can stop working if dirt, engine grease, and dust end up accumulating. This will trigger the car alarm and if cleaning doesn’t help then the sensor is not properly connected.
  • Boot sensor: It is a switch that senses an open or closed boot. When the boot is open, the sensor closes the switch and illuminates a warning light on the dashboard. With a defective boot sensor, the car alarm goes off at random times.

You can fix this by cleaning the dirt or dust accumulated on your boot latch and the sensor by using a brake cleaner and a cleaning brush. If the car alarm continues to go off, your sensor might be damaged and requires replacement. For the boot latch connection, make sure it is functioning smoothly instead of the wires showing signs of tamper.

Faulty key FOB

Usually, there can be an issue with the Key FOB (Frequency Operated Button). The battery can be low or dead after a long usage period. To avoid having the key fob send incorrect and unnecessary signals to the car, triggering the alarm, you can replace the battery.

You can even have it reset or checked if there is some other malfunction.

Poor car alarm installation

Usually, old cars are not installed with an alarm system and you need to have it installed after purchase. So you can try installing it yourself, however, if not installed properly the alarm will go off at any unexpected moment.

Even insurance doesn’t count when you neglect to properly install the alarm system. Thus, you can have a professional mechanic install it and if you had previously visited a mechanic to have the alarm system installed, then you should go back and ask them to rectify the issue.

How to switch off your car alarm?

You can try following some of the points given below to switch off your loud car alarm:

  • Turn on your car.
  • Lock or unlock your doors.
  • Disable the car alarm manually.
  • Disconnect the car battery then you can remove the fuse from the alarm system (if visible).
  • Check the alarm system manual to reset the alarm system.
  • Remove the defective car alarm system.

Remember, that a car alarm is an important part of your car as it defends itself and alerts you of any intrusion. If you are having trouble, it could be some animal or someone could be doing specifically to lead you to remove or disable your alarm system. Some cars have an extremely sensitive alarm system, thus it could go off if a large vehicle ramble by or someone happens or touch it accidentally.

Hence, take quick precautions by getting your alarm system repaired as soon as possible, especially when you notice a rise in the frequency of the alarm system going off randomly.

Also read: Phone charging but CarPlay not working: Quick Fix

Sania Usmani

Sania Usmani

Always curious, calm, and a little crazy, you can find me daydreaming or studying. An avid reader, traveler, and graduate of Aviation Science, I love gaining new experiences in life and star gazing. You can contact her here: