Car Alarm Keeps Going Off – 14 Causes And How To Fix It

If you are seeing your dash lights flashing and you have a horn that is beeping intermittently, then it is a good sign your car alarm keeps going off. It could be that someone is messing with the alarm or it may be malfunctioning completely. Thankfully, there are several things that you can do to troubleshoot the issue before heading straight to the auto parts store.

14 Causes Why Your Car Alarm Keeps Going Off

Nonfunctional Key Fob Or Faulty Key Fob

Nonfunctional Key Fob Or Faulty Key Fob

If your car alarm keeps going off, the first thing to check is whether the remote keyfob is working or not. Many people don’t realize that if they leave their keys in their pocket or purse, the remote keyfob may not be able to communicate with the vehicle’s computer system. In most cases, this will result in constant alarms which cannot be stopped until you locate your keys and start communicating with your car model again.

Defective Or Dirty Hood Latch Sensor

Defective Or Dirty Hood Latch Sensor

Another possible cause for an alarm to go off constantly is a faulty hood latch sensor which detects whether or not the hood is open or closed (usually via magnet). If this sensor fails to detect an open hood properly, it will trigger an alarm every time someone opens their hood to check something under it. This is usually easy to fix by replacing the defective part or cleaning it thoroughly (if possible).

Poor Hood Latch Connection

Poor Hood Latch Connection

When you go to start the car, the alarm goes off. The most likely cause of this is that the hood latch is not properly securing the hood to the front fender. If this is the case, then you need to check the connection between these two parts and make sure they are securely connected together. If they are not, then you will need to replace them or tighten them up so that they fit better together.

Faulty Door Lock Sensor

Faulty Door Lock Sensor

If your car’s security system has a faulty door lock sensor, then that could be another reason why it keeps going off. You need to check whether this is broken or not. Sometimes, if it is damaged, then it will send false signals to the central control unit and cause the alarm to go off unnecessarily.

Low Battery Level

Low Battery Level

If the battery level is low, it can cause your car alarm to go off. If it’s at a critical level, the alarm will automatically go off as a safety measure. In this instance, it is imperative that you replace the faulty automobile battery immediately. If you don’t have an extra one, you need to get one from your local auto parts store or mechanic shop.

Dead Battery In Key Fob

Dead Battery In Key Fob

If there’s no power coming from the key fob, it will cause your car alarms system to go off. You need to check if there is still power in the key fob before trying anything else. You can either open it up and check or take it to your local auto parts store or mechanic shop and let them check for you.

Corroded Or Rusted Battery Terminals

Corroded Or Rusted Battery Terminals

The corrosion on the battery terminals can cause your alarm system to malfunction which will result in an endless beeping sound from your car’s speakers until they are cleaned up and repaired properly by a professional mechanic at an auto shop.

Weak Or Overly Sensitive Sensor Connection

Weak Or Overly Sensitive Sensor Connection

A sensor is what triggers the alarm to go off when someone touches it. If the connection between the sensor and the control module is weak or overly sensitive, then it may trigger when you don’t want it to. If this happens, you can either move the sensor away from whatever it’s near or adjust its sensitivity setting so it doesn’t go off as easily.

Disconnected Circuitry Or Wiring Problems

If any of the wires that connect your car’s electrical systems are disconnected or broken, then they won’t work properly and may cause an issue with your alarm system as well.

Disconnected Circuitry Or Wiring Problems

For example, if there’s no power going through one of these wires, then that means there’s no power going through its corresponding circuit breaker or fuse as well — which means none of those components will work either! If you suspect this might be happening in your case, call a mechanic immediately who can check out all of your wiring connections and make sure everything is still connected properly.

Bad Alarm Control Module

Bad Alarm Control Module

The alarm system’s brain is the control module. The system may not function correctly or at all if it has a poor one. In most cars, the module may be found either beneath the dashboard or under the hood. A qualified technician can test and replace it if necessary.

Problematic Control Module

Problematic Control Module

If your car alarm that keeps going off randomly when you don’t want it to, check to see if there is a problem with your control module. You can find out by taking your vehicle to an auto repair shop for diagnostic testing and repairs if necessary.

Incorrect Installation Of The Alarm

Incorrect Installation Of The Alarm

Incorrect alarm system installation is another typical source of this issue. You will need to re-install it again but this time make sure that everything is connected properly before turning on your car or starting your engine otherwise there might be some damage done to your vehicle’s electrical system which could cost more than just replacing an old control module or battery!

Low Car Battery

Low Car Battery

If your battery is low, the car’s computer will try to draw more current than what the battery can provide. This will cause the alarm system to go into “fail-safe” mode and set off the alarm. The best way to fix this problem is by getting a jump start or taking your car to the mechanic for an inspection.

Sensitive Shock/Movement Sensor/Shock Sensors

Sensitive Shock or Movement Sensor or Shock Sensors

Most cars have movement sensors buried in the seats that detect any sudden movements in front or behind the car. If someone bumps into one of these sensors, it will trigger an alarm even if there is nothing wrong with your vehicle. To fix this issue, simply place tape over each sensor so no one can bump into them anymore!

How To Turn Off Car Alarm

Turn Your Car On

Your automobile should be started immediately if the alarm goes off. This will usually cause the alarm to stop.

Lock Or Unlock Your Car Doors

You can also turn off the car alarm by locking or unlocking your car doors. If you lock all of your doors, the alarm should go off; if you unlock one of them, it should go off as well. You may also try locking and unlocking the door a second time if that doesn’t work.

Look For The Shut-off Switch

Some cars have a shut-off switch located on or near the ignition key cylinder. You’ll need to consult your owner’s manual or call a local mechanic for help locating this switch if you don’t see it immediately.

Remove The Alarm Fuse

Another way to get rid of a car alarm is by removing its fuse from under your hood or dashboard paneling. You’ll need to consult your owner’s manual or call a local mechanic for help removing this fuse if you don’t see it immediately.

Pull The Wires

Pulling the cables that link the automobile alarm to the battery is one of the simplest methods to disable it. This will stop any electrical current flowing through the system, disabling it completely. You’ll need some basic knowledge of wiring in order to pull these wires correctly. If you’re not sure what you’re doing, take your car to a mechanic or auto shop and ask them to help you out with this task.

Reset Your Car Alarm System

Another way that you can turn off a car alarm is by resetting it using a remote key fob or another device that allows you access to your vehicle’s electronics remotely. Most modern vehicles use car key fobs with buttons on them so that owners can lock and unlock doors without having to physically touch their cars all day long.

Completely Remove Your Car Alarm System

If the alarm is triggered by motion or by opening a door, you can easily stop it by getting out of the car and closing all the doors. Then lock all doors with the key fob or manually. If you’re parked in a garage and don’t want to walk around with keys in hand, try using the door opener button. Press it once to unlock all doors, which will cause the alarm to stop sounding.

What To Do If Your Car Alarm Keeps Going Off?

Charge The Battery & Check The Charging Voltage

The first thing that you should do is check to make sure that there is enough charge in your car battery. This can be done by simply turning on your car and then checking the voltage reading when it starts. If there is not enough voltage coming from your battery, then you will need to either charge it or replace it with a new one. If there is enough voltage coming from your battery but still have issues with your car alarm going off, then there might be another problem causing this issue.

Using an OBD2 Scanner, Look For Any Error Codes.

If you have an OBD2 scan tool, you can check for trouble codes that might be triggering the alarm. If there are any, try clearing them with a code reader or using the manufacturer’s diagnostic software.

Lubricate All Door Hatches & Locks

Door hatches and locks can fail over time due to a lack of lubrication or abuse. Check them all and add some grease if needed. You may also want to replace any broken or missing parts (such as door lock actuators).

Check The Sensitivity Setting

Most modern alarms have multiple sensitivity settings so you can set them for different situations like when you’re home versus away from home or leaving your vehicle unattended at night. Try adjusting these settings until the problem stops happening.

Change The Key Fob Battery

If changing the sensitivity setting doesn’t help, change the battery in your key fob. If there are still problems with false alarms after doing this, contact an auto repair shop for further assistance.


What Do You Do if Your Car’s Alarm Goes Off at Night?

Three things to do if your car’s alarm goes off while you’re sleeping:

  1. Stop the vehicle and look around. If you’re parked in a quiet area, it’s possible that something has fallen onto your car or that someone is trying to break in.
  2. Check inside your car. Sometimes keys or other objects may accidentally set off an alarm if they fall into certain areas of the vehicle.
  3. Call the police if you’re still unable to locate anything. In this type of circumstance, they’ll know what to do.

Is It OK To Drive With A Faulty Car Alarm?

A faulty car alarm can be a real pain, but it’s not worth risking your life over.

If you hear a beeping noise when you unlock your car, or the lights flash and the horn goes off for no apparent reason, then you need to contact your local auto electrician immediately.

A faulty car alarm is dangerous because if it starts beeping whilst you’re driving, it could distract you from the road and cause an accident. And if the horn goes off while you’re inside your car, then this could cause panic and make people think that someone has broken into their vehicle.

Can A Faulty Sensor Trigger The Alarm On Some Vehicles?

The answer is yes, a faulty sensor can trigger an alarm on some vehicles.

In most cases, the sensors that trigger the alarm are located on the doors and they will beep when you open the door. This is to alert you that the door is not fully closed.

There are other types of alarms, such as those that protect against theft of your vehicle or break-ins. These types of alarms may also be triggered by a faulty sensor in some cars and trucks. A faulty sensor may set off one of these alarms on your vehicle if it does not work properly or if it is damaged in some way.


If you’re having problems with your car alarm keeps going off, it’s a good idea to get it checked out as soon as possible. Most of the time, there’s nothing to worry about, but it’s better to be safe than sorry and bear the costs of a seemingly unnecessary repair. Not only that, but consider whether or not you really want an obvious car alarm, as it could attract unwanted attention from criminals who assume that you are away from the car when you are actually nearby.

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