8 Reasons Your Car Alarm Keeps Going Off (and How to Stop It)

There is now a wide range of car alarm systems to choose from. Simple systems are activated by car vibrations. Even more protection is promised by systems that monitor the interior using ultrasound and are activated or deactivated via the central locking system. But a car alarm that doesn't work at all or doesn't work properly can be extremely annoying to you and your neighbors.

Depending on the design of the system, movements and manipulations with doors, the bonnet, the tailgate, vehicle movements, the interior and manipulation of the battery will trigger your alarm going off.

What triggers a car alarm?

An alarm system on the car has built-in functions that monitor the current flow of the car. If, for example, the interior light is switched on, the system notices this low current flow and triggers an alarm. In addition, most car alarm systems have door contact monitoring.

Modern alarm systems not only trigger the alarm when the vehicle is tilted, i.e. supposedly being towed, but also when movements are detected in the interior. If something moves in the vehicle, the alarm system is triggered. Once the alarm has been triggered, it can never be switched off from the inside.

However, in most cases, the alarm system is not triggered by a break-in, but by wind or vibration. 

If a car is a bit old, older cables and contacts can lead to leakage current. This then causes false alarms. To check if the error comes from there, consult your car manual. If your alarm system is monitored by the on-board voltage, the false alarm of your alarm system is very likely to come from there. It is recommended that you check the cables and contacts and replace them if necessary.

Newer alarm systems have an ultrasonic function. However, the device also has a certain tolerance in order not to react too sensitively. This is the case, for example, with a fly. However, if this sits directly on the ultrasonic sensor, the alarm goes off.

How to stop the car alarm?

The following steps will help you reset your factory alarm. Some of these tips may apply to car alarms as well, but if you are having trouble with your aftermarket alarm it is best to consult a manual.

Method 1: Reset the alarm remote control

It is possible that the key fob or alarm remote control has failed and is not sending a proper signal to your vehicle's alarm system. When this happens, your vehicle's alarm may go off unintentionally without you wanting it to.

Method 2: Reset the alarm

Some of the more common alarm resets involve less complicated techniques that can be completed in minutes. First, unlock the car. Sometimes an alarm goes off when you try to lock and unlock the car manually. When the vehicle senses that the key has been inserted into the lock, the alarm can turn off. Second, start the car. You can also try turning on the car to reset the alarm.

Method 3: Disable the alarm

If your alarm is a constant distraction and goes off often and spontaneously, you may want to disable the alarm entirely. Note, however, that disabling the alarm will deprive your vehicle of one security feature. You should consult a mechanic before deciding to completely disable your alarm.

Note: Be aware that some alarm systems work in conjunction with your vehicle's ignition. This means your vehicle may not start if you tamper with the alarm.


Which cars have the alarm system most often?

Land Rover, Porsche, Mazda, BMW, and Audi (source: Statista). Of course, other modern cars have immobilizers and alarm systems.