The alarm goes off on its own: possible causes, solutions and recommendations

A car alarm is installed for the safety of the vehicle. She must always be on guard. But the security system itself can malfunction and work incorrectly. This situation needs to be corrected as quickly as possible, because attackers can take advantage of this state of affairs and quickly steal a car.

Most often, the alarm goes off on its own. Many motorists face this problem, but few of them know what to do. We decided to correct this situation.

Causes of abnormal alarm reactions

There are a large number of reasons why the alarm turns on automatically in a car. This circumstance significantly complicates diagnosis, identification of the true cause and its further elimination. Below we have provided a list of the most common circumstances that can cause a similar problem:

• failures in regulating the sensitivity of sensors that monitor impact, tilt and rolling;
• rattling of sensor contacts that control the process of closing the trunk, doors and hood;
• low or complete battery discharge and leakage in power circuits;
• the car parking area is in the zone of electromagnetic interference, which, at a high level, can disrupt the operation of the alarm system;
• problems with electrical wiring;
• unstable operation of the CAN bus;
• moisture on the main unit of the security system;
• problems with the volume sensor;
• Attackers can also cause abnormal system reactions.

Any of these situations can happen to anyone in their life. We simply must consider each of these reasons and give advice on how to eliminate them, which will be useful in practice.

How to find a fault in a car alarm

Before starting to repair a car alarm, you need to find the cause of the malfunction. Completely different breakdowns can have the same symptoms. To accurately determine the cause of the malfunction, it is necessary to consider all possible options step by step.

You need to start with the keychain. Inspect it for mechanical damage and traces of water. If the key fob gets into water, condensation will form on the inside of the display cover. The operation of such a device (if it turns on) will be unstable. If the key fob does not fall and falls into the water, but the display is turned off and nothing happens when you press the buttons, then the culprit is a low battery.

If the key fob is fully operational, but nothing happens when you press its buttons, then there may be two reasons for this - strong external interference or problems with the car and the alarm system. Try bringing the key fob to the part of the car where the car alarm antenna is installed and press the button. If nothing happens, then faults must be looked for in the machine itself or in the alarm equipment installed on it.

Next, power and wiring diagnostics are performed. Check the battery charge and inspect its terminals for oxidation. The full charge of the battery can be easily determined by the operation of the on-board electronics. If everything is normal, then the next step is to check the wiring. To do this, you will need a special tester that calls contacts. Inspect the wires for mechanical damage. Special attention should be paid to fuses. They are usually found in a box, which is located on the wire coming from the positive terminal of the battery.

If the cause has not yet been found, then a defect in the control unit or a malfunction of its software is to blame. You won’t be able to eliminate such a defect with your own hands, but with a software failure everything is much simpler - you just need to carry out simple manipulations, which we will discuss below.

What to do in these cases?

As you can see, there are many reasons. Each of them affects different worker nodes. Elimination of each of these causes is carried out differently. Therefore, we have no choice but to consider each of the possible options.

Deliberate actions of car thieves

This reason for the alarm system to be triggered is a classic, the most common case. Typically, car thieves use a standard scheme. They operate at night, when you can take the car owner by surprise and his reaction to what is happening is not entirely adequate. The car alarm goes off as if by itself several times. Usually, after three alarms, the owner concludes that the system is faulty. The anti-theft system is turned off, and the owner continues to dream, deciding to start repairs in the morning.

The problem really disappears in the morning, however, along with the car. You need to be vigilant if you want to keep your property safe and sound. To activate the security system, attackers use various methods; their professionalism and ingenuity are growing by leaps and bounds.

In such cases, you need to act as follows:

• How to set up a Starline alarm if it goes off on its own

• under no circumstances should the alarm be turned off;
• you can use the quiet mode, which is found in many modern systems;
• we go down to the car and investigate the situation, if necessary, call the police.

Incorrect shock sensor sensitivity adjustment

This mechanism is sensitive, even very sensitive. Therefore, the alarm may be triggered during bad weather. Many modern systems are equipped with two-level sensors, for example, Tomahawk alarms, which rarely go off on their own. The sensitivity of such systems is adjusted at the installation stage of the security system. With high sensitivity, false activation is possible.

In case of emergency situations, the sensor can be disabled software or technically. The sensor is usually located under the steering control and is presented in the form of a small block. It is equipped with a connector and an LED. The design is equipped with adjustment holes that require the use of a small “plus” screwdriver. The process of adjusting the sensitivity level is carried out according to the instructions that come with the security system.

Not only incorrect adjustment of the sensor can cause incorrect operation. The sensor may not be installed correctly. Plastic clamps are usually used for its installation. Over time, they become unusable, and the sensor dangles without any fixation. In this state, it can be triggered even by a light breath. The solution to the problem is simple - replacing the fixing clamps.

Contact bounce of door, hood and trunk sensors

This problem is most often encountered by owners of cars manufactured before 2005. Such machines have contact sensors or limit switches that quickly become unusable. Such a malfunction can be determined by the vehicle’s intermittent alarm setting. Initially, the sensor on the driver's door fails, since it is used most often.

The problem is solved by adjusting the curtains and brackets on the door locks, which are located on the counter. In most cases, this resolves the problem. Another solution is to replace the limit switches.

As for more modern cars, electronic mechanisms are already installed here. If the alarm does not work correctly due to these reasons, then you have to completely replace the lock blocks.

Low battery

The operation of a car alarm directly depends on the battery, or rather on its charge. Discharge of the battery to a critical level entails malfunctions in the operation of the car security system.

If the system is bidirectional, then most likely its design includes a mode that indicates the voltage in the on-board network. When the indicator drops below 11.5 Volts, the key fob signals its owner with a sound alert. In the case of simple systems, the siren may be activated at low voltage.

The car owner must check the voltage on the battery and diagnose the power circuit, which may contain leaks. Signals with very low energy consumption are now being produced. An example of such a system is the Panther car alarm, which itself goes off extremely rarely. Such devices can work for up to six months, but this requires a good battery and a working power circuit.

• What to do if the alarm goes off?

Car alarm Panther

Electromagnetic interference in a parking lot

The technical data sheet, which is necessarily attached to the security system by the manufacturer, indicates the permissible level of electromagnetic interference and the noise immunity indicator. In many populated areas, especially in large cities, there are places with high electromagnetic field strength. In such conditions, malfunctions of the car alarm may occur.

Such places are often located near the following objects:

• points for receiving and transmitting cellular signals;
• power lines;
• overpasses along which public transport travels (trolleybuses, trams).

There is only one solution to the problem - look for another parking lot. There are no other options.

Bad contacts

A problem of this nature arises in the case of improper installation of a security system, which was carried out by craftsmen without specialization and experience. Electrical installation rules are violated and the car owner has to deal with incorrect work of the secret police. But even with proper installation, problems may arise after 5-7 years of active use. During this time, contacts and connections become unusable and require replacement. Even a reliable Sherkhan alarm can go off on its own due to problematic contacts.

There may be two options here:

• contacting auto electricians who will diagnose the system and replace faulty connections and contacts;
• installation of a new system.

The latter option often turns out to be more rational, which is why more car owners choose it.

Car CAN bus malfunctions

The CAN bus is a local automotive network that connects the vehicle’s control units into a single system. Previously, security systems received sensor information from each door. Now systems collect information about the car via the CAN bus. The information is complete and extensive, covering all data that relates to the car.

Vehicle CAN bus

In most cases, the CAN bus is presented in the form of a twisted pair with different levels. If the integrity is violated, the signal is lost and does not reach the security system. She perceives this state of affairs as the actions of attackers.

It is very difficult to return the CAN bus to its previous functionality. There is no way to do this without the services of a specialist. You need to be patient and be prepared for serious financial expenses.

• GSM car alarm - main nuances

Moisture on the main alarm unit

Owners of old cars face this problem. To install a security system, a place is often chosen under the instrument panel in the area of ​​the left pillar. Moisture penetrates the pillar located on the driver's side. In the fall, this problem occurs more often than in the rest of the year, since falling leaves form blockages in structural drains.

What to do if the alarm goes off on its own precisely because of moisture? First of all, it is necessary to clean the drains. This will avoid the problem. If there is already water in the block, proceed as follows:

• turn off the car;
• remove the battery terminals;
• disconnect the alarm unit from the connectors;
• disassemble the case, act carefully;
• clean the board using a soft bristle brush and medical alcohol, never use a solvent;
• leave the board to dry;
• We assemble the unit, connect it and check the operation of the system.

Volume sensor malfunction or incorrect installation

Such a mechanism is not installed on every car and it is not found in every security system. You need to be able to install it correctly. If errors were made during installation, the alarm will beep at every passerby. In such cases, the sensor must be turned off and in a quiet situation, away from crowded places, experiment with its location.

A working, correctly installed alarm system is the key to your peace of mind and the safety of your car. Do not ignore the false activation of the secret police. It is necessary to deal with the problem that has arisen, carry out diagnostics and eliminate the cause of incorrect operation. You shouldn’t accumulate problems; it will only be even more difficult to eliminate them in the future. And they will not disappear on their own either.

Car drivers > Useful information > Accessories and gadgets for cars > Alarms > What to do if a car alarm goes off by itself

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The safety of the vehicle directly depends on the reliability of the car alarm.

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If the alarm starts to go off from time to time without the participation of the vehicle owner, you should immediately establish the reasons for the abnormal operation and begin to eliminate them immediately.

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Problems with signals from different manufacturers

The reasons why the alarm goes off on its own vary from brand to brand.

Why does Starline A91 turn on and off by itself

In order for the Starline alarm to stop spontaneously triggering on the car, it is necessary to check the correct installation and secure all its parts tightly. This is due to the fact that the sensor’s operation is based on the piezo effect - the sound pulse reaches it even before the impact.

To prevent the Starline system from triggering for no reason, it is also recommended to adjust the sensitivity as follows:

1. Reduce the indicators of both zones, while adding a few points for the warning zone (located opposite the green indicator).
2. Then the alarm is activated in the “Permanent security” mode.
3. After 1 minute, you need to hit the car to understand what level of sensitivity is set - sufficient or excessive.
4. If necessary, reduce the indicators again.

In order for the Starline A91 car alarm to stop triggering spontaneously, exactly the same actions are performed to adjust the “Alarm” zone.

Good to know

The maximum value of alarm and warning sensors is 14, the minimum is 0.1. When selecting “0” the sensors will be disabled.

Why does the Tomahawk 9030 scream without hitting the car?

Drivers note the following reasons why the Tomahawk alarm constantly goes off on their car by itself:

1. Mounting the sensor on a plastic surface. When the plastic cools down, it makes clicks, to which the alarm reacts. To eliminate the malfunction, the device should be secured to a metal part of the body.
2. On Kalina, the Tomahawk 9030 alarm starts going off for no reason at regular intervals. This situation repeats itself mainly at night - at 0:15, 1:15, 2:15, etc. Most likely, the clock or timer was set incorrectly. The problem is solved by resetting all settings to factory settings.

Spontaneous activation Sheriff

Possible reasons why the Sheriff alarm goes off on its own:

1. In rainy weather, it can turn on the “Alarm” mode when large drops hit the hood of the car (when installing the system under the dashboard). The problem is solved by reinstalling the sensors in the middle of the body.
2. The lamp is in the “Light up when the doors are open” mode. If you install a diode in it, the Sheriff alarm will stop triggering the interior lighting.

Turning on the Alligator car alarm by itself

To solve the problem, first of all, you need to pay attention to the sensitivity sensor settings.

If the Alligator alarm still turns on by itself after adjusting the sensor, you need to change its location and check the condition of the limit switches.

Response of the Pantera security installation

The problem areas of this security system are the limit switches - they often break or the connections on them oxidize. Therefore, it is necessary first of all to check their integrity and, if necessary, clean them well.

If the Panther alarm goes off on its own for passing cars, you need to adjust the sensitivity sensor. Also, for a complete diagnosis, you can check the insulation and wiring connections.

What to do if Shere Khan 5 constantly reacts to opening the door

If the Sherkhan 5 alarm goes off on its own to open the doors, you must:

1. Disable Hands Free and Passive Staging.
2. When opening the doors, pay attention to whether the ceiling light turns on. If not, put the door switches in order.
3. Check that the system is installed correctly. This phenomenon can be observed when only the driver’s door is protected, and the alarm does not respond to all others (including the trunk).

Malfunctions in the operation of the Pandora alarm

If the Pandora alarm constantly goes off on your car for no reason, you should pay attention to:

1. Temperature conditions at which it is operated. According to drivers' reviews, despite the operating capacity stated in the instructions from +40C° to -40C°, the alarm begins to work incorrectly even at a temperature of -20C°.
2. Where to wear the keychain. If it is always near the ignition key, problems may arise there, since when driving it will constantly hit the panel.
3. Signal connection method. On some new cars it is recommended to connect the central locking not via the CAN bus, but via wires. The choice between a digital or analog connection should be made only after pre-installation testing of the car in all modes (rest state, engine start).

Photo gallery: troubleshooting various alarm elements

Reduced sensitivity on the shock sensor

Shock sensor regulation principle

Alarm horn repair

In the photo - repair of hood switches

Why does the alarm go off on its own?

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The most possible causes of abnormal operation of a car alarm include:

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• Incorrect sensitivity adjustment of the shock/tilt/roll sensor;
• bouncing of the contacts of the door, hood, trunk sensors;
• battery discharge, leaks in power supply circuits;
• high level of electromagnetic interference in the car parking area;
• poor contacts, faulty alarm wiring;
• malfunctions in the car CAN bus;
• moisture ingress;
• malfunction or incorrect installation of the volume sensor;
• deliberate actions of car thieves.

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Let's figure out what to do in each specific situation, how to establish the cause of false or pseudo-false positives.

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What to do in these cases

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Let’s try to figure out what can be done first in such cases and what the nuances are.

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Deliberate actions of car thieves

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The situation is classic and has been described more than once in the media, literature and films. A classic situation: the car alarm starts to go off periodically at night. After the third or fourth alarm, the owner, thinking that the signals are false, disarms the car, postponing fixing the problem until the morning.

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In the morning the problem goes away along with the car. Hijackers provoke false positives for their own illegal purposes.

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How pseudo-false positives are usually caused:

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• throwing small objects at the car;
• special transmitter of powerful radio interference;
• installation of a vibrating device on the bottom, etc.

What to do in such cases? Under no circumstances should you completely disarm your vehicle. In most car alarms, for such a case, a “quiet” operating mode without a siren is provided, which can be programmed from the key fob.

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As a last resort, you can go down to the car and turn off the siren by hardware: disconnect one of the conductors going to it. The residents' peace of mind will be restored, and the alarm will continue to operate.

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When installing a car alarm, it is advisable to choose a model that has an immobilizer function. In this case, if unauthorized entry occurs, starting the engine will be problematic. However, this will not protect the car from theft by towing or towing. Typically, car thieves abandon their plans when the hazard warning lights are on, which attracts attention at night.

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Incorrect shock/tilt/roll sensor sensitivity adjustment

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Increased sensitivity of the sensor can lead to false alarms in bad weather conditions (wind, heavy precipitation), arming near highways, busy places.

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In modern car alarms, two-level sensors are mainly used (for weak and strong influences). Their sensitivity is set when installing a car alarm, usually by adjusting potentiometers located on the sensor body. If the sensitivity is high, this may lead to false alarms.

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In an emergency, you can temporarily disable the shock/tilt/roll sensor programmatically or do it technically (disconnect the connector from the sensor).

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The roller sensor is usually a small matchbox-sized unit mounted under the steering wheel, with a connector and an LED on the housing. The body has one or two adjustment holes for a small “plus” screwdriver.

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The sensor sensitivity is adjusted in accordance with the operating instructions.

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A common cause of false alarms is a malfunction of the sensor. Sometimes (and most often) it is attached to the body structure elements with plastic clamps, which break off after a couple of years of operation. The sensor simply hangs on the wires, triggered by the slightest breath of wind. Therefore, it is necessary to check the quality of its fastening.

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Contact bounce of door, hood, and trunk sensors

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This malfunction is more common in cars produced before 2005. In such cars, contact sensors (limit switches) were installed for closing doors, hood and trunk, which often became unusable. A sign of a problem with standard door closing sensors is inconsistent arming of the car.

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First of all, the driver's door closing sensor usually fails, as it is the most popular. In this case, closing the doors with the central lock, they can open immediately.

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Video - what can be done if the alarm goes off on its own due to the limit switches on the hood and trunk:

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The curtains and door lock brackets installed on the pillar should be adjusted; the problem is usually eliminated. If necessary, limit switches can be replaced.

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Modern cars use electronic sensors for closing doors and windows, so if the alarm system malfunctions due to them, it is often necessary to replace the entire lock assemblies.

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Battery discharge, leaks in power supply circuits

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If the car battery is discharged to a critical level, the car alarm may begin to work abnormally.

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Bidirectional alarms with an LCD key fob usually have an on-board voltage indication mode. If it is lower than 11.5 Volts, the key fob beeps. In simpler alarms, a siren may be activated. In this case, it is necessary to check the voltage on the battery and the power circuit for leaks that lead to discharge of the battery during parking.

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Modern car alarms have extremely low current consumption in security mode (up to 15 milliamps). If there are no leaks and a good battery, such car alarms can work for up to six months while the car is parked for a long time without recharging the battery.

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High level of electromagnetic interference in the parking area

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Manufacturers indicate in the technical specifications the level of noise immunity of car alarms. In urban environments, there are areas in which the level of electromagnetic field strength significantly exceeds the maximum possible, which can lead to failures. Typically such areas are located near:

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• cellular base station transceivers;
• power lines;
• trolleybus and tram overpasses;
• industrial zones.

The only way to eliminate false alarms associated with this reason is to look for another parking spot.

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Bad contacts, faulty alarm wiring

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Often, an alarm system is installed on a car by non-specialists, with violations of electrical installation rules. Even if it is installed correctly, after five to seven years of operation the alarm system begins to “fail,” most often due to broken contacts and connections. Therefore, every year more and more car enthusiasts apply for orders to dismantle old alarm systems.

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In some cases, it is more rational to completely dismantle the old one and install a new car alarm than to constantly contact auto electricians to fix problems with an alarm system installed several years ago.

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Car CAN bus malfunctions

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Modern car alarms collect information about vehicle systems via the CAN bus. A CAN bus is a kind of local car network that connects the main control units of a car (body, engine, ABS, etc.)

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If earlier alarms controlled the closing of doors directly from the sensors of each door, then modern alarms operating via a CAN bus receive almost all data via it simultaneously: about the condition of the body, the temperature of the cabin, the engine, and others.

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Typically, the CAN bus is a twisted pair of low and high levels. If its integrity is violated, the signal about the state of the car’s security zones is lost; the car alarm can identify a condition such as an attempt to enter and begin to go off.

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Restoring the integrity of the CAN bus is a rather complex problem and requires the intervention of a specialist.

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Moisture on the main alarm unit

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A very common cause for older cars.

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A typical installation location for a car alarm is under the dashboard in the area of ​​the left pillar near the driver’s left knee. Moisture penetrates into the installation area along the driver's pillar. Most often, the problem occurs in the fall, when structural rainwater drains under the windshield become clogged with fallen leaves and pine needles. At this time of year, drains must be cleaned periodically.

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If, however, water gets into this alarm unit, then you need to turn off the ignition, remove the battery terminals, and disconnect the car alarm head unit from the connectors.

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Then you need to carefully disassemble the case, clean the circuit board with a soft brush and medical alcohol (not solvent!), dry it, you can use a hairdryer at a temperature not exceeding 130 degrees Celsius.

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Volume sensor malfunction or incorrect installation

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The volume sensor is not installed on all cars. In Sherif ZX 945 car alarms, for example, you can find such a sensor.

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If it is not positioned correctly in the car, it can trigger on passers-by. In such situations, you can temporarily dismantle it, then in a calm environment experiment with the location of the volume sensor.

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Complaints from car owners

Mostly, car owners complain about breakdowns such as:

1. In most cases, the key fob does not work correctly: the doors may open with a huge delay, or the central locking may not turn on at all. The problem is most likely in the central unit, which is responsible for controlling the security system, or in the key fob. We try to bring the key fob near the vehicle, and if in this case everything works well, or something may clog the signal, or the key fob needs to be changed. In other options, repair of the central control units of the anti-theft system is required.
2. Another much more common reason is that the alarm goes off on its own. In most cases, this becomes the reason that you cannot get into the vehicle, or even worse, during the period of your absence from the signal, the battery of your vehicle has completely discharged. In most cases, this is not even a malfunction as such. In some cases, when the correct alarm setting can solve the problem. For example, most likely the system turns on on its own if its sensitivity is set to the maximum range; you just need to reduce it and everything will be in perfect order. Although, let's look at all the possible situations of this breakdown in detail.

Methods for dealing with car alarm malfunctions

You can give different advice on repairing signaling, but first of all you need to understand that there are a huge number of reasons why the system breaks down, because we are talking about electronics. If the power unit is blocked, there is no need to immediately replace the alarm; it may make sense to diagnose the immobilizer. It happens that disabling it and reactivating it helps solve the problem.

If the engine starts successfully, but the key fob does not allow sending commands to the central unit, then there are several methods to solve this problem:

1. First you need to bring the key fob as close as possible to the antenna adapter or control module. Perhaps the reason lies in the weak signal.
2. Another option is to try to reboot the anti-theft system, as mentioned above, to do this you need to disconnect and reconnect the battery.

Often, our compatriots encounter problems with the system as a result of dead batteries in the remote control. Failed elements should simply be replaced. It also happens that the system refuses to receive a signal if the car is parked in an area of ​​increased electromagnetic sensitivity. The electromagnetic field contributes to the formation of interference, and accordingly, the signals that you send from the key fob will be clogged.

Photo gallery “Repairing the signaling system”

If the battery charge has become critically low, this will also lead to a failure of the alarm; as a rule, this problem occurs if the voltage in the on-board network drops below 8 volts. In this case, the car alarm siren may also sound. As a rule, alarm manufacturers themselves configure this function so that the siren is activated when an attempt is made to break into the car and disconnect the battery. First of all, you should check the battery charge and replenish it if necessary.

Another problem, which is more relevant for older cars, is damage to the central unit or its operation in moisture conditions. For example, in VAZ 2108, 2109 and 21099 cars, as well as other models, the central unit is usually placed under the steering wheel, on the left. The hood opening cable runs directly above it, connecting to the regulator. If it’s raining outside and the driver opens the hood, moisture can get into the cabin through the cable, which subsequently gets onto the control module. Constant exposure of the block to water leads to its failure.

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What are the reasons for the alarm to turn on spontaneously?

As experienced drivers say, there are only three main reasons that the anti-theft system turns on independently:

1. Damage to the alarm or some sensors. You can only fix the breakdown at a car service center; you can take advantage of warranty repairs, which will not cost you anything. The only problem is that you won’t be able to identify such breakdowns on your own; you can use the help of a qualified specialist.
2. Items that are left in the vehicle interior. If the luggage is very large, it can send an alert to the internal volume sensor, in which case the anti-theft system will work independently.
3. Incorrect operation of the door trunk or hood switch. Then, when the alarm turns on, an icon will appear on the screen indicating that the door or trunk is open. The main reasons are: oxidation or severe wear of the limit switches. You can lubricate the part with an anti-corrosion fluid, but it is recommended to completely change it - this way you are guaranteed to solve the problem.

The alarm can turn on by itself even during precipitation. The reason is water, which ends up in the system and disrupts its normal operation. There is only one way out: turn off the anti-theft system and give it time to dry completely.

Excessive sensitivity of the alarm system sensor. This breakdown can be corrected by correct system settings - we just reduce its sensitivity.

What malfunctions occur most often?

• Nutrition. The alarm does not respond to your clicks, or performs actions that you did not order. We start checking with the key fob, namely the battery. It won’t take much time to disassemble the key fob and replace the battery. A characteristic sign of a low battery is that the LED becomes dimmer or the remote control range of the key fob decreases. Another reason for the key fob not working may be water getting on it (when used in the rain).
• Wiring. No matter how complex or advanced the car alarm is, be it a regular AOS beeper (car alarm) or a GSM alarm, under the influence of external factors, the contacts at the connection points always oxidize. That is, car alarm repair always begins with ringing the contacts.
• The LED lights up brightly, but the alarm does not respond to pressing. In this case, we begin car alarm repair by finding out the reasons for this phenomenon. The “brain” of AOS could freeze, because in any case we are dealing with a mini-computer. Reboot required. It is necessary to remove the terminal from the battery (any), i.e. de-energize the system and after a couple of minutes put it back on. If the alarm works, you can fix the terminal; if not, try rebooting 2-3 more times. If this doesn’t work, then we move on to the next stage of car alarm repair – checking the fuses.
• Circuit breakers. If there is a separate wire with a separate mounted fuse block from the positive terminal of the battery (or from wires with a constant “plus”), check the fuse. Since we have already started, at the same time we need to check the serviceability and functionality of the main energy consumers of the car (standard fuses): emergency lights, sound signal. During this test, the power supply is dialed negatively (this type of testing can be carried out if you know where the central AOS unit is located). In this case, the AOS is rebooted using the following method: remove the connector from the unit and reconnect it. If the beep goes off, no big deal.

If your efforts to repair your car alarm are not successful, you will have to contact a car service center; the cause of the malfunction turns out to be deeper.

How to set up an alarm?

Thus, if the anti-theft system turns on by itself, most likely the main reason is the sensor is not working properly. Basically we are talking about the shock sensor, the sensitivity of which we will need to reduce. Ideally, this sensor is triggered only during a strong impact on the vehicle body and does not howl from wind gusts, fireworks, or sounds from a vehicle passing nearby. If you installed a shock sensor consisting of two levels, then it is triggered in these options.

But it can only send a signal with the help of headlights - after blinking a couple of times, there should be no sound signals, and besides, there should be no howling.

Sometimes some models of budget alarms can reduce the sensitivity of the sensor quite easily. Thus, let’s consider the answer to the question of how to set up an alarm when it goes off spontaneously:

1. First, let's find just the sensor. Basically, it is located in the interior of the vehicle, mainly among the front seats, right under the manual brake.
2. Having found the sensor, we look at a special rotary type regulator located in the upper area. We rotate it in the opposite direction counterclockwise, which reduces the sensitivity of the alarm system.
3. If the above methods do not help, then it is better to re-enable the sensor - just turn it off and on again. Most likely, the sensor freezes a little and this can solve the problem.

In a premium alarm system, things are not so easy. Settings there are carried out using special software, directly through the central control unit of the system. It is better not to do this on your own, but rather to entrust all the work into the hands of professional employees. Otherwise, if you interfere with the operation of the alarm system, you may risk damaging the system and you will lose the warranty that is provided when purchasing the system.

What to do if the shock sensor triggers for no reason

The most common problem that owners of an alarm system from Starline with a shock sensor encounter is a false alarm. It occurs even in devices that have been installed recently. As a result, the sensor goes off on its own and the alarm screams, although no one is nearby.

To fix the problem, the first thing you need to do is figure out what the warning signs were for the appearance of a false signal. Did this happen at a time when other people's cars were passing nearby? Or during certain weather events.

The time of day when such incidents occur plays a role. And also how often they happen. In some cases, false alarms occurred when the car's handbrake was engaged. To accurately determine the reasons, all details are important.

Another problem is a violation of the design of the sensor or module associated with external damage or wear. Replacing or repairing broken parts will help fix the problem. The signal is also triggered due to the interception of radio waves when the module and sensor loops are close to each other. To eliminate it, just separate them.

If the sensor is constantly disconnected, then the reason may lie in improper mounting. For the latter, I use plastic, which is deformed and destroyed due to impacts or other external influences. The plastic mount can be replaced with a metal one.

The best way to test the serviceability of newly installed sensors is to test at minimum sensitivity. If a reaction is observed even with minimal settings, then the system will probably need to be replaced.