What to do if the alarm light is constantly on
Most modern cars are equipped with factory alarms. Often the car owner buys a used car with an alarm system already installed. In both cases, the car owner may not know all the intricacies of his vehicle’s security system. The constantly lit alarm light is a sign that the car’s security system is broken. In such a case, it is necessary to understand the causes of the constantly working light and eliminate them in order to restore the performance of the system.
Main causes
There are several main reasons why the security system indicator lights constantly unblinking.
- The most common reason for the constantly lit alarm indicator light is intentionally or accidentally activated Valet security system mode. In this mode, the indicator light is permanently lit. However, the car is not armed. The car owner is notified about the activation of such mode by the inscription on the electronic display of the alarm key fob.
- Another common reason for the constant burning light is the failure of limit switches (limit switches) of the opening parts of the car body, that is, in the doors, trunk or hood.
- A less common, but still common cause of a constantly lit light is a software failure, a hardware error of the alarm system or the failure of individual sensors.
For some models of alarm systems, the constantly lit indicator can be associated with the activation of certain security system modes: “Panic”, “Free hand”, with the enabled immobilizer, with remote engine start, etc. In this case, it is quite easy to remove the constantly lit indicator. You need to switch the alarm to the standard security mode or disable it for a while.
Valet mode in the alarm system
Various manufacturers of security systems for cars lay in the software several modes of illumination of the indicator of the alarm. In different modes, it blinks, is at rest or is permanently lit. Most manufacturers of alarm systems have a service mode Valet, when the car is unprotected.
Valet mode is used mainly for service and repair of the car when the alarm system can hinder workers of car service. Valet can be switched on by car owner either intentionally or accidentally, in this case alarm indicator light constantly on informs that the car is unprotected. In this mode, the car owner can only remotely open and close the door, trunk and hood locks.
On some models of alarm systems is enough just to switch on Valet mode, as it is activated from the remote control by pressing combination of keys. On other models of alarm systems it can be started only from the button inside the car.
How to disable Valet
The option of deactivating Valet mode depends on the possible ways of enabling it. It is deactivated either by pressing a button in the car interior or with the remote control of the alarm system by pressing a combination of buttons.
Button to toggle Valet mode
The “Valet” button can be located anywhere in the car: both in the cabin, as well as in the luggage compartment or even under the hood. It is often hidden in a particularly inconspicuous place so that potential hijackers were not tempted to disable the entire security system by simply pressing a button.
As a rule, during the alarm system installation, the service staff ask the car owner about the desirable location of the button, where to switch the Valet mode on and off. In case the owner of a car does not know where such button is, he/she will have to look for it. The most expected locations of the button are the following places.
- Under steering column is the most trivial location of the button, which is also the most insecure. The area under the steering column is convenient because the driver can press it without leaving the driver’s seat. However, potential hijackers look for it there in the first place. As a disguise, the button can be covered with an ordinary plug, which will also prevent accidental pressing.
- Under the driver’s seat is another convenient, but banal option, which is also often masked by a plug.
- In the driver’s door is a questionable option, as in this case it is possible to access it from outside the car.
In general, the placement of the button is limited only by the imagination of the person on whose initiative the alarm system was installed. Therefore, in order not to waste time on an empty search, it is better to carefully study the technical documentation of the alarm system.
Disabling Valet mode with the help of a button almost all manufacturers of car alarms looks the same.
- It is necessary to start and then turn off the car engine.
- After 10 seconds, you need to press the Valet button and hold it for a few seconds, or move the switch to the “Off” position.
- The driver is notified of the mode off by a double klaxon beep, after which the indicator light turns off.
Combination to activate Valet
Another option for disabling the Valet mode of the car alarm system is possible with a remote control, that is, a key fob. To do this, press one of the combinations of keys key fob, with this for different manufacturers of security systems combination of keys, as well as the sequence and duration of pressing can vary significantly.
Exact combination of keys to disable the service mode in a particular model of security system can be found in the manual for the car alarm system. Combinations of keys of the most widespread car alarms are as follows.
- In popular Scher-Khan alarm systems enabling and disabling the Valet mode is performed by pressing and holding buttons 1 and 3 for a second. Do not overdo it, because when you press these buttons for 2 seconds will turn off the shock sensor.
- Valet mode in StarLine alarms is disabled by pressing button 2 once.
- In Tomahawk car alarms mode is disabled by pressing button Z, usually you need to press twice – once once and once with the button held. In some models of the company’s alarm systems, the way of disabling may differ, so you should first study the manual of the particular security system.
- In Alligator alarm systems the mode is deactivated by simultaneously holding down for 3 seconds the buttons 2 and 3.
Mechanical damage to the alarm system
Mechanical damage which is indicated by constant illumination of the LED is usually caused by door, tailgate or hood limit switches. The limit switches are simple open-close sensors, which are buttons connected to the alarm system. When closed, they are in the pressed position and close the electrical circuit, when open, they open. The cause of damage to the limit switches can be:
- oxidation of the contacts in conditions of high humidity or during the winter;
- loose fit due to deformation of the body part as a result of an accident or improper installation;
- Breakage due to mechanical impact or shock.
When the power supply is disconnected, the alarm system perceives the body part to be open. As a result, the alarm indicator light illuminates with a steady light.
On modern vehicles equipped with a display, identifying the problem of a non-functioning limit switch is easy enough. A door or body part with a non-functioning limit switch will also appear as unclosed in the graphic representation of the car model.
To solve the problem, visually inspect all of the vehicle’s limit switches for oxidized contacts. If an oxidized limit switch is detected, it must be disassembled and the contacts cleaned.
If mechanical damage is the cause of the faulty limit switch, it must be replaced with a new one. If an incorrect positioning of the limit switch is detected, adjust the position of the limit switch to the required position for proper operation.
Faulty programs or sensors
A rather rare but possible reason for the constant illumination of the indicator is the failure of the software or the failure of individual sensors. The special sensors of the security system include sensors of mechanical impact (impact), changes in the interior volume, body position, etc. In case of breakage of one of the sensors, the system perceives the situation as emergency and informs the car owner by means of indicator. In this case you will have to go to a specialized service to diagnose a faulty sensor.
Also permanent indication can be caused by a software or hardware error in the electronic control unit of the alarm system. You can try to reset the alarm by disconnecting the power to the battery. If the problem remains, it is difficult to solve it yourself, so it is better to contact a service center
In any case, the constant burning of the indicator lamp is a sign that the car is not reliably protected by the alarm system, therefore, reducing the safety of car ownership. Finding the cause of the constant burning of the indicator light and eliminating it, you can return the reliable protection of the car with a car alarm system.
Constantly lit alarm light – causes and ways to solve the problem
Under normal conditions, the car alarm system will go off when it senses an “intrusion” above its normal threshold – thanks to the shock sensors that most modern cars have. It can be triggered by a loud sound or other significant impact striking the car.
A car alarm also goes off when a person tries to break into a car, thereby alerting the owner to the crime in progress and helping to prevent the theft. But what should you do if the alarm light stays on all the time, even when everything is fine?
Main causes
Some alarms include switches on the hood, trunk or doors of your car. If the switch goes off – for example, if the door is open – the alarm sounds. Standard car alarms use voltage sensors. If these sensors detect a sudden drop in voltage – for example, when a door is opened or when a light comes on – an alarm will sound or an indicator light will come on.
Different manufacturers use different systems to alert the driver to the danger. For example, Pandora alarms have a special red light that indicates loss of communication with the key fob. Tomahawk alarms also have a single light bulb. But here you can determine the mode of operation of the alarm system only after its removal.
The main reasons why the alarm light is constantly lit:
- VALET mode;
- mechanical damage to the alarm system;
- Faulty programs or sensors.
Let’s consider each of them in more detail.
Valet service mode
Service mode Valet (or simply Valet) is built into almost every alarm system and is designed to diagnose or analyze the performance of the system and other important components.
Valet service mode also changes the way the alarm light works. For example, the light can be permanently lit when the motor is off, and immediately extinguished when the ignition is on.
Activation is done with a combination of keys on the key fob. If the alarm light is permanently lit, you need to simultaneously press two buttons, less often – sequentially press certain keys. In older models of cars, the button for switching to service mode was placed somewhere in the cabin, but this method was abandoned long ago. If your keyfob has a digital display, the symbol Z will appear on it when you switch to Valet mode.
Deactivating Valet mode with the button in the passenger compartment
If you’ve purchased a used car, look for a button in places like this:
- Under the steering wheel. This is the most convenient and easiest place for a criminal. Look for inconspicuous plugs or recesses.
- Under the driver’s seat. Carefully inspect the driver’s seat and look underneath for plugs.
- In the door.
The easiest way to quickly find the Valet mode button is to carefully study the manual for the installed alarm system. You can get all the information you need from the service center and on the internet, on the manufacturer’s website.
To put the car in or out of service mode, you need to press the button for 10-15 seconds. When the mode is activated, the lights will flash and a special sound will be heard.
Deactivation of service mode with a combination of keys
Here are a few examples of how to turn off popular alarms from service mode:
- Tomahawk. Press the Z key several times. Sometimes you need to first press the button for 2-3 seconds, release it and press again briefly.
- Star Line Twage B6/B9. Press button 2 until you see the signal to exit the service mode.
- Pandora. Service mode can only be used by an expert in the service center. If you find problems with keyfob and alarm system communication, contact your mechanic.
- Scher Khan Magicar 5/6. Press buttons 1 and 3 simultaneously.
When the service mode is removed, the light will stop illuminating. If the problem persists, contact the service center.
Mechanical damage to the alarm system
Now that we’ve learned what causes a car alarm to go off under normal circumstances, let’s now talk about why the alarm light sometimes goes on for no apparent reason. The first and one of the most common reasons for a blue alarm light to go off is a faulty key fob. This is the device that allows you to lock or unlock your car door with the push of a button. For newer cars, having a fob inside the cabin allows the driver to start the engine.
If your key fob is not working properly, it may send the wrong signal to your car. Sometimes it may even send that signal without pressing a button. Such signals can cause the alarm light to go off for no reason. The quickest way to solve this problem is to replace the batteries. If that doesn’t solve the problem, you can try resetting the unit or use a programmer to figure out what’s wrong with it.
Faulty programs or sensors
An alarm light going off without the slightest warning can also cause battery problems. The first reason a battery can cause this trouble is if it is low on electrolyte. You may not know this, but car alarms weren’t just made to warn of theft or burglary. The light bulb can also signal other problems in your beloved car. One of these problems is a low battery.
In some cars, if you try to start the engine with a “dying” battery, an alarm will go off. Be sure to check your car’s battery level with a voltmeter if the light comes on for no apparent reason. If the charge is less than 12.6V, you need to replace it. It would be wise to install a new battery instead of waiting for your car to stall in the middle of the road while driving.
If your car’s battery is dead, you can use several connection cables. Every car owner should have them handy. Determine which terminal is positive and which is negative. Connect the red terminal to the positive terminal of the discharged battery, and do the same with the other end of the wire, connecting it to the charged one. Take the black cable and connect one of its clamps to the negative terminal of a running battery. Instead of connecting the other end to the negative pole of the discharged battery, attach it to the bare metal surface of the “discharged” engine. This can be a bolt or a screw.
Be sure to make sure that everything you attach the clamps to is clean of dirt.
Once all the connections are in place, the next step is to start the engine of a running car. Let it run for a few minutes. After a while, start the engine of the “dead” car and let it idle. Wait 5-10 minutes and disconnect the cables. First remove the black clamp from the car you were charging. Then remove it from the “good” battery. Finally, remove the red clamp from that battery and finally remove the red clamp from the previously discharged battery.
Rusty battery terminals can also be the cause of a constantly lit alarm light. If your vehicle’s battery terminals are covered in rust, they will not be able to send the proper amount of power where it is needed. If this happens, the car’s sensors may interpret this as a low battery and activate the alarm. What should you do in such a case? Try to keep your battery terminals away from substances that can cause rust, especially oil and grease. This can also happen if the battery terminals start to wear out.
Dirty hood lock sensor
Another reason why the alarm light is constantly on is an improper signal from the hood. This can be due to damage or improper maintenance. Hood locks need to be wiped down regularly because this is where dirt from the road and car engine accumulates. If the dirt gets too much, the alarm system can give a false light signal. This is because your car’s sensors may think the dirt and debris on the hood latch comes from someone trying to get into the interior.
Another benefit of keeping your lock sensor clean is that it helps prevent unintentional hood openings. A well-maintained lock sensor correctly detects when someone is trying to break into your car. This keeps not only your property safe, but also you.
If the alarm light stays on even after you’ve cleaned the hood lock sensor, the problem may lie deeper than just dirt. The system may not be detecting the signals correctly. Such a problem may even affect other parts of the car. For example, you may notice improper indicators, such as the airbag light, when in reality they are fine.
The easiest way to fix this is to disconnect and then reconnect the sensor that is near the headlights. If that doesn’t work, it may be time to visit your mechanic.
