Why is the alarm not. If the alarm key fob does not work

When the car owner cannot "negotiate" with a capricious security system, one has to turn to service station specialists. But what to do when the problem arose far from civilization? Experts advise not to panic and try to fix the "glitch" that has arisen on your own.

The door opens but the alarm does not work

One of the most common car alarm malfunctions is “silence” when opening the doors or trunk of a car. One of the signs of this problem is that the interior lighting does not light up when the door is open, as well as the absence of a corresponding indication on the instrument panel. Most motorists will immediately go to the service station, hoping that specialists will solve the problem in a few minutes. But you can perform simple steps yourself to return the alarm to its original performance.

First you need to turn off the alarm so that it does not work during repair work. It is enough to put it in standby mode and do maintenance.
The next step is to unscrew the alarm limit switches connected to the doors, hood and trunk. Then they are disconnected, the wire chips are disconnected.
Using fine sandpaper, the contacts of the limit switches are cleaned.
Using a tester or test light, you can check the integrity of the wiring and the health of the sensors.
It remains to assemble the alarm in reverse order, turn on the security system and test it in different modes.
If broken limit switches were found during the disassembly process, then you should purchase new parts in the store and introduce them into the alarm.

Problems with turning the alarm on and off

Often, car owners receive complaints about the difficulty of turning on or off the alarm. For example, when you press the key fob button, the system does not react in any way. Sometimes the owner of the car cannot get into the car, and sometimes it remains in the parking lot without protection. Experts advise paying attention to such probable causes.

The car alarm system is poorly configured. Because of this, the signal to open or close the machine is not triggered in time.
A fake security system is installed on the car, which cannot perform its tasks.
The installation of the alarm system was carried out in an artisanal way, some sensors are hidden in the back of the car. A weak signal simply does not reach the sensor.
A common problem is a dead battery in the remote control.
For older protection modules, a typical cause of signal delay is changes to the control unit.

If none of these reasons is visible in a particular car, then it is better to contact an experienced master. Sometimes you have to change individual elements of the system or reconfigure the alarm.

Unpredictable alarm behavior

A common "glitch" in many alarm systems is its complete disobedience to the owner of the car. For example, while the car is moving, the protective module is triggered, the doors or the engine are blocked, the siren turns on, the lighting blinks, etc. With such symptoms, the algorithm of actions is as follows.

Check the state of charge of the battery. It is a dead battery that often causes unpredictable behavior of the security system.
Find the alarm control unit and check the reliability of the contacts. One of the chips may fall out, causing the module to behave inappropriately.
If in the future it is planned to replace the alarm, then you can ask the service station master to block the operation of those functions that do not work in time.
When none of the manipulations gave a positive result, it is necessary to replace the security module. This is the only way to prevent accidents on the road.
You can temporarily turn off the alarm by pulling the wires out of the control unit or by simultaneously pressing a specific button combination.

Depending on the situation in which an unexpected operation of the security system occurred, the car owner can call in a service station or fix the problem on his own. Clear and quick actions will help get rid of communication with police officers.

There is no sound and light accompaniment

A typical "glitch" of car alarms is the lack of sound and light when turned on. The reason may be quite banal, so you should immediately look under the hood.

One of the possible reasons may be a loose or oxidized contact on the control unit. It is easy to remove corrosion products or carbon deposits with sandpaper, rags and solvent.
Carefully inspect should be the wires connecting the security module with the dipped beam relay or "emergency gang". Damaged wires are recommended to be replaced.
The cause of the malfunction may also be the control unit that controls the operation of various sensors and relays.
A faulty relay, to which the wire from the alarm is connected, also leads to the loss of sound and light signals.
Unexpectedly, the siren may fail due to a breakdown of the device or oxidation of the supply wire. To test the siren, you must directly apply voltage to the contacts.

A malfunction in the alarm system can give the car owner a lot of unpleasant minutes. It is not easy to find a breakdown due to the many possible options. Sometimes a familiar electrician, armed with a tester, solves the problem within a dozen minutes. But it happens that a real council of specialists gathers at the service station, trying to solve the riddle of the security system. It is important for the car owner not to get confused when a "glitch" appears, to turn on his brain and ingenuity in a timely manner.

As you know, a car alarm is an electronic device that reacts to attempts of illegal intrusion into your car. A little earlier, we already wrote about this device and the problems that cause false alarms, but today I would like to talk about the opposite malfunction - the failure of the security system. Why this happens and how to deal with it, you will learn from this article.

1. Common causes of alarm failure

Any problems with car alarms are most likely the result of inattention and untimely maintenance of the system. On the theoretical side of the issue, the problem can appear anywhere, but in practice, especially taking into account the quality of modern electronic components, any “breakdown” is not only the negligence of a motorist who, for example, replaced the battery in the control key fob at the wrong time, but also the result not too high quality parts produced today. Of course, the cheaper the device, the more problems arise in its operation.

The most typical signs and their corresponding causes of “unexpected” car alarm malfunctions include:

Lack of response to the control panel (key fob). In such a situation, first of all, you need to check the power supply of the device. If everything is fine with the battery, make sure the buttons are working, as it happens that they sink and touch the contacts inside the case. In the absence of obvious deformation of the battery and mechanical damage, it makes sense to purchase a new remote control and “register” it in a program that coordinates actions.

In addition, there are cases when the elements of the device are exposed to strong external radiation. Given that the alarm unit consists of rather peculiar parts, it is not surprising that it is not protected from external influences, which often interfere with the operation of the alarm, and sometimes even disable the microprocessor, that is, the basis of the unit. In urban conditions, indeed, serious radiation is very rare, therefore, cases of device breakdown due to its impact are often expressed in the disappearance of the “firmware” from the unit’s memory, and without this program the device will not work. As a rule, such a breakdown is eliminated by a service specialist where this alarm was installed by “flashing” the electronic unit.

Lack of response to a blow to the body (if a shock sensor is installed). This type of malfunction is most often the result of an illiterate installation and configuration of the security system - in particular, the shock sensor settings, the parameters of which are not always configured correctly.

Lack of response of car doors to "commands". If there are no problems on the part of the control unit, the place of signal loss should be sought between it and the electromagnetic drive. In the case when all the electrics are intact, and when current is supplied from an alternative source, the drive is triggered, it is worth looking for a problem in the alarm unit. Perhaps it is he who sends an impulse to block the door.

No siren signal when the alarm is triggered. In this case, it is quite possible that the siren unit simply does not receive current, which means that you need to look for a break in the wiring. Not every car owner can independently detect the cause of an alarm malfunction, and if you already understand at the initial stage of repair that your knowledge may not be enough for this, it is better to immediately contact the service where the alarm was installed.

2. What should I do when the alarm suddenly refused to work?

First of all, there is no need to panic, even if problems with the system appeared halfway to the house. Suppose that the alarm system does not respond to the "instructions" of the key fob, and you cannot install or remove the security system. Provided that the battery is charged and there is no second key fob, you can try to restore the operation of the remote control in the following way. First, check (and, if necessary, replace) the battery. And do not forget about the type of battery, because even 12-volt key fobs can have different sizes and be powered by 6-volt or 3-volt batteries with different types of housing. Moreover, even if the diode glows, this does not mean at all that the battery is “good”, even if it is new.

The state of this battery depends on a number of factors, for example, on the period and temperature of storage, the quality of the material used, etc. Naturally, if you buy a part in the winter at the market, when the temperature is below zero, and it is sold, as they say, “from the hands”, then somehow you can’t expect a long service life from such a battery (if it works at all).

So it turns out: the battery seems to have been replaced, but the remote control still does not work. In such a situation, it is likely that the device will need to be programmed. Often, all the required actions are described in the operating instructions for the alarm and provide for a “forcible” opening of your own car. And then, to the sounds of a siren, it is necessary to turn off the system using the “Jack” service mode button (the need to manipulate the ignition is also possible). But here, too, there is one problem: you also need to know where to look for the aforementioned button.

The specialists who installed the alarm, the former owner of the vehicle, or the same operating instructions for the system can help with solving the problem. The specified control helps to carry out an emergency shutdown of the alarm and the subsequent programming of functions in the memory of the control unit. If it is impossible to perform the specified action (for example, you still could not find the button), you should turn off the power supply of the insulation along with the interlocks and immediately go to the service station.

In addition, there is such a thing as a "freeze" key fob. There can be many reasons for this phenomenon. For example, the vehicle is in the area of operation of powerful radio transmitters, when starting the car engine, synchronization failures are caused by a run-down battery, and some, especially “sensitive” systems, cannot stand repeated pressing of the remote control buttons outside its coverage area. Most often, in such cases, the above-described algorithm for emergency unlocking of the alarm is used, after which, having driven off a little, you can once again check the operation of the key fob. Once the instrument has started working, it may require a few quick button presses or a re-sync.

Consider another possible variant of the appearance of problems in the operation of the security device. Imagine that the car has stalled (or you yourself have turned off the ignition), and when you try to start the vehicle, the security system signal is triggered. The reason for this behavior most often lies in the lack of battery charge: the battery is dead - the car will not start. In turn, the alarm responded to a low voltage (below 8V), which is programmed in the system to prevent a hijacking attempt by removing the terminal from the battery. In such a situation, it is necessary to turn off the siren and troubleshoot the battery.

Summing up all of the above, it should be noted that the most common cause of problems with car alarms is the lack of response of the system to the “commands” of the remote control, which are expressed in the failure of the arming / disarming function of the car. What you need to do: bring the remote control (key fob) closer to the location of the central unit and try to press the buttons again. It didn’t help - reboot the system by disconnecting the battery terminal, because often the causes of failures are radio signals from large industrial facilities that “jam” the key fob signal.

Here, in fact, are all the main causes of possible car alarm malfunctions. Of course, like all other breakdowns, malfunctions in this system are an annoying nuisance, but you still should not panic, since malfunctions can be eliminated by repair and reconfiguration. In some cases, you can restore the system's performance on your own (when it comes to conventional devices), while in others it is better to seek help from professionals, especially when it comes to complex GSM alarms.

Car alarm - a device that allows you to protect the "iron horse" from hijackers and intruders who are trying to get into the car. Situations may occur when the alarm ceases to function stably. For example, when returning to a parked car, pressing the key fob button does not turn off the alarm. After that, the driver tries to open the door with the key, and the alarm starts working. The article will discuss how to turn off the car alarm in such cases.

The problem of a non-working alarm is easy to solve. The main thing is to know the sequence of actions. Photo: news.pn

Why is the alarm not working?

Radio interference. In large cities, there are many operators of mobile networks, reinforced concrete structures, car parks. It is they who can cause malfunctions in the operation of the alarm system, creating interference. In this case, you can turn off the alarm by approaching the place where the anti-theft protection system is installed. It is necessary to direct the key fob to the alarm unit and press the button to turn it off.

Dead battery. The alarm may stop functioning if it does not have sufficient power supply. To restore its work, you need to recharge or purchase a new battery.

If the car alarm does not turn off, you should check the condition of the battery, which is located in the key fob. Photo: cartore.ru

Problems with the power supply of the alarm key fob. First of all, when you press any of the buttons on the key fob, the indicator lamp should light up. In more advanced versions of the alarm, on the keychain with a screen, there is information about the low battery. In both cases, it is recommended to take it out, knock lightly and insert it back.

In winter, during frosts, the key fob can also fail, for example, after a long stay on the street. To do this, you need to place the alarm key fob in a warm place, which will allow you to “warm up” its battery and turn off the protection system.

Ways to turn off the alarm

If after the above diagnostics the problem is still not resolved, you must disable the alarm manually. First of all, under the hood you need to find a place to install the alarm. This is followed by de-energizing the contacts of the speaker emitting the siren.

The Valet button is better to hide not in the most obvious place. Photo: car-key.by

Disabling the alarm can be done using a special hidden button, which is located in the passenger compartment, under the instrument panel. It's called Valet. The rules for using this button can be specified in the instructions that are attached by the car alarm manufacturer. If it is absent, then after detecting the button, you must perform the following options:

Turn on the ignition, quickly press the button and turn off the ignition;
Turning the ignition on, quickly pressing the button four times and turning off the ignition;

If there is an alarm with the GSM communication standard, it is necessary to read the instructions, which indicate the instructions for entering the pin code. After its introduction, the vehicle starts and the alarm loudspeaker is connected.

In any case, try to act according to the instructions that came with the alarm.

Below we will tell you how to deal with the most common alarms.

Disabling the alarm of popular models

Starline (525)

To turn off the alarm, you need to follow the instructions, according to which you need:

Opening the car interior;
Turning on the ignition;
Holding the service button for no more than 6 seconds. If the above actions are performed correctly, the car will emit a sound signal, and the indicator on the key fob will flash occasionally.
Switching off the ignition.

Chinese clones perform quite well on the market. Pay attention to the Porsche clone -.

Starline (A6)

Disabling this alarm model is different in that it is unlocked using a special code. To enter it, you must comply with the following algorithm of actions:

Opening the car with a key;
Turning on the ignition;
Pressing the Valet button for at least 20 seconds. The first digit of the code means the number of clicks;
Pressing the button again. The number of clicks corresponds to the second digit of the code;
Switching off the ignition.

Tomahawk (RL950LE)

Two sound and light signals of the car will indicate the successful deactivation of the alarm. Photo: aries-auto.ru

To completely disable the security system of this model, follow the following sequence of actions:

Opening the car with a key;
Turning on the ignition;
Four times pressing the service alarm button;
Switching off the ignition.

Sheriff

This alarm model is quite common. To unlock it, you need to do:

Opening the car with a key;
Turning on the ignition;
Pressing the service button of the car alarm;
Turn off the ignition and turn it on again;
Pressing the Valet button again;

The above actions will help bring the alarm out of a faulty state into repair mode, which will allow you to start looking for problems in its operation.

ALLIGATOR (D-810)

This alarm has two shutdown modes - standard and service, which is activated using a special code. To turn off the car alarm in standard mode, you must:

Use the key to open the car door;
Turn the key, turn on the control lamps on the instrument panel;
After 10 seconds, press the Valet button;
Switch off the ignition.

To enter the security system into the service mode, you should:

Open doors with a key;
Insert the key and turn on the ignition;
Turn off all control lamps by turning the key to its original position;
After a few seconds, press the alarm service button. The number of clicks is equal to the first digit of the code;
Turn the ignition on and off;
After waiting up to about 10 seconds, press the Valet button. The number of clicks corresponds to the second digit of the code number;
Turn off and turn on the ignition.

If you enter the wrong code more than three times in a row, the car alarm system will be temporarily unavailable.

The transition to the service mode of this alarm is quite complicated, unlike models from other manufacturers.

ALLIGATOR (LX-440)

To put the model in question into service mode, you need to sequentially execute:

Opening the door with a key;
Activate all control lamps on the dashboard with the ignition key;
Pressing the Valet button;
Switching off the ignition.

The emergency shutdown of a car alarm from this manufacturer is carried out in this way:

Opening the car door with a key;
Turn the ignition key until the control lamps turn on for a while (up to 10 seconds) and turn it off;
With the ignition already on, hold the alarm service button for at least 10 seconds until the car beeps. It will mean that the alarm has switched to maintenance mode.

If your alarm remote control has stopped working, pay attention to this video:

Outcome

Despite the variety of existing manufacturers, models of car alarms, their maintenance and repair is almost the same. It is important to know where the Valet alarm service button is located in the car. With its help, you can turn off a faulty alarm with your own hands. Therefore, it is important to know the features of the transition to the service mode of a particular model of the car's security system.

The alarm system is the most widespread means of protection of the car from malefactors. Her work is controlled remotely using a remote control, which is commonly called a "key fob". Like any electronic system in a car, the alarm can fail. Problems with it begin unexpectedly, and when leaving home or from work, the driver may find himself in a situation where the alarm does not respond to the key fob. In this case, the car will have to be opened with a key, but you need to figure out what the problem is, so as not to have problems with the alarm in the future.

Why the alarm does not respond to the key fob

Not a single master will be able to immediately name the exact reason due to which the alarm does not turn off when the corresponding button on the key fob is pressed. Possible causes will be listed below in order of prevalence, from most common to rare.

Keychain problems

The first thing to check is the key fob itself, since in most cases the problem is with it. There is a good chance the batteries are dead.

You need to inspect the keychain. If it has a screen, you need to check if it lights up when you press the buttons. When there is no screen, you can look for a diode on the key fob, which is often installed to signal the driver about the lack of charge in the batteries installed in the remote control.

If there are no new batteries at hand, you can use the common "charging" method. It is necessary to remove the batteries from the key fob and knock them a little against each other or on another hard object. After that, you need to correctly install the batteries back into the key fob and try to remove the alarm from the car.

The key fob itself, or rather the transmitter installed inside it, may also fail. This problem occurs if an attempt was often made to transmit a signal by pressing the button on the remote control. For example, a button could spontaneously be pressed in a pocket. In this situation, you can try to remove the alarm from the spare remote control, if any.

Dead car battery

The second most common problem, due to which it is not possible to remove the alarm using the key fob, is a dead or heavily discharged car battery. In such a situation, you can try to get closer to the car and press the key fob button. In some situations, this will remove the alarm, but with such a battery, the engine is unlikely to start.

Please note: This problem occurs frequently due to the inattention of drivers. Many drivers forget to turn off the lights when turning off the engine and parking the car. Because of this, the battery charge is completely spent on lighting, especially if you leave the car like that for several hours or days.

radio interference

The radio wave signal can be "jammed" for various reasons, and if the driver of the car is in such a zone, it will be difficult to remove the alarm. For example, radio waves are deliberately jammed near airports, military installations, and important government facilities. You can check the operation of the radio waves on your mobile phone by looking at the quality of the connection and the operation of the GPS.

To remove the alarm in such a situation, it is recommended to bring the key fob as close as possible to the signal receiver and try to send a command.

Lost connection between key fob and control unit

Due to a software failure, communication between the control device (key fob) and the signal receiver (alarm control unit) may be lost. In such a situation, the only way to fix the problem is to reprogram the bundle. To do this, it is necessary to turn off the alarm control unit in emergency mode (by pulling the wires out of it), and then synchronize it with the key fob. The driver can program the alarm key fob on his own, you just need to find the manual for the device of a specific manufacturer.

Important: In rare situations, the loss of communication between the alarm key fob and the control unit may be accompanied by the loss of software from the device's memory. In this case, it will not work to synchronize the remote control and the ECU on your own, since you will first need to restore the device firmware in a service center.

Problems with car electronics

If the vehicle has faulty wiring or other electronic problems, even when the engine is off, this can be affected. For example, there will be a power surge in the alarm control unit, which will lead to its failure, as well as serious wiring problems.

The alarm control unit itself may also be faulty, which will disable the wiring. In this case, often before failure, the driver can recognize that trouble will soon happen. The signs of a malfunction of the control unit are its strange “behavior”: the alarm turns on for no apparent reason, the system does not respond correctly to commands from the key fob, some functions fail completely. If there is a suspicion that the control unit will soon fail, you need to send it to a service center for diagnostics.

What to do if the alarm does not respond to the key fob

The alarm is accompanied by a loud sound, which must be turned off as soon as possible. If you open the door with a key, the sound will not disappear, but there are two effective ways to turn off the alarm in this case:

After the alarm can be turned off, you should go for diagnostics to determine what the problem was.

The alarm goes off on its own

Another common problem that drivers have to deal with is the alarm going off for no apparent reason. There are three main problems that lead to such alarm operation.

Contact failure

If the car is operated carelessly or in bad conditions (for example, in high humidity), the contacts of the buttons may be oxidized, from the operation of which the alarm receives a command. Most often this happens with the locking buttons, the hood is open or closed. The alarm may be triggered if it receives information due to corrosion of the contacts that the hood is opening. In such a situation, it is necessary to replace the limit switch.

Problems with door mechanisms

Sometimes a situation arises in which, by pressing the key fob, a notification appears that the car is unlocked, but in reality this is not the case. In this case, you need to check whether the central lock is working (you can do this by ear). If there are no problems with it, you need to check the fuses and, in extreme cases, the wiring. In cold weather, this situation can be observed due to the freezing of mechanisms.

Incorrect operation of sensors

Cars are crammed with sensors, and the alarm is guided by the readings of many of them. If the shock sensor is configured with increased sensitivity, the alarm will work by itself all the time - from the wind, falling leaves, air flow from a passing car, and so on. In this case, you need to adjust the shock sensor or others that can trigger the alarm.