Let's find out how to install an alarm with auto start on a car?

In this article, auto electrician Alexey Molotov answers the question “Which alarm system should I install with auto start?”

Hi all! Friends, winter is approaching, I began to think more and more often about autorunning the “Snowman”. I went shopping, searched, asked for a simple autostart unit that would simply start the engine when the temperature dropped, but as it turned out, there is no such thing, they are all connected to the alarm. Why was I looking for just a launch unit, you ask, but because I am an opponent of alarms, well, I don’t trust electronics 100%, better in the old, old-fashioned way. But now I understand that it won’t work out that way, so the question arose, which alarm system is better? Who can advise what?

What to consider when designing an autostart?

Such a system can be made if there is data on the time during which the engine starts. It should be noted that the gap can be any, it depends on the condition of the piston group, ignition and fuel supply systems. The reference time value is about 0.7 seconds from the moment the crankshaft begins to rotate until the final start.

It is these data that should be taken into account when designing an autostart system. If the time is within acceptable values, then car alarms can be used. But if it is larger, you will need to dodge, come up with a design that can provide a guaranteed launch. Another option is to use a cell phone. But you can also connect a relay with a delay. The main thing is to close its contacts for the period of time that you need.

How to choose an alarm

If a car owner decides to install an alarm in his car, the first problem he faces is choice. How can you decide, because there are so many offers around. And every advertising poster assures us that this particular alarm system is the best; by installing it, we don’t have to worry about our car at all.

In order to understand which system should be connected, we first need to figure out who we want to protect ourselves from:

1. Petty swindlers, rummaging through glove compartments, twisting car rims. Such people can be scared away simply by a flashing light simulating an alarm.
2. Thieves who open cars in order to remove the car radio. They have gotten used to bypassing alarms and within 5 seconds, breaking the glass with their heads, they pull out everything valuable from the car. There is only one way out - do not leave expensive items, bags and other valuables in the car and install an alarm system from the car factory.
3. There are craftsmen who, having broken the glass, get under the hood of the car and cut off the power. There are a lot of them and you should protect your car from such hunters. They have their own work points and yards. If a car has an alarm system installed without a car factory, the owner will not notice all these maneuvers.

Using a car alarm

If you need to start an installation located in close proximity to you, then it is quite reasonable to use the simplest car alarm. It has two channels: the first is used for disarming and arming, the second is for additional functions, such as auto start or opening the trunk. These are frequently used functions that are required for normal operation. But you can also do autostart from your phone yourself, this allows you to increase the crankshaft cranking time.

But the downside is that the pulse generated at the contacts of the second channel has a short period of time. Usually this is 0.7 seconds, but some car alarm models allow you to program and select one of several options. The maximum contact closure time can be 3 seconds.

Why install an alarm

Of course, the decision about whether an alarm connection is needed or not is made by the car owner. Many drivers say that a car alarm or any other is a waste of money. However, installing even the simplest security alarm can scare away intruders. Sometimes, seeing a flashing light on the windshield of a car, thieves will bypass such prey. Of course, there is a category of advanced hijackers and robbers who are capable of hacking the most complex systems, but these are a minority.

If a system is installed that not only signals an intrusion, but is also equipped with additional functions, it will significantly facilitate some aspects of operating the car.

These functions include:

• Remote control of central locking;
• Glass closer;
• Turbo timer;
• Automatic interior and exterior lighting;
• Automobile plant.

Correct alarm connection

But not every car alarm model allows you to connect the outputs of the second channel to a powerful consumer, such as the winding of the retractor starter. Therefore, it is necessary to use additional devices - relays with normally open contacts. It must be connected correctly, and the entire ignition system must also begin to function. Therefore, there is a need to use additional relays, the contacts of which will close when a signal is sent to autostart the engine, assembled with your own hands.

The relay windings are connected to the positive terminal of the battery. The control is done in minus mode, this will be much safer. The wires coming from the second signaling channel are connected as follows: the first - to ground, the second - to the terminals of all used relays. The contacts of these devices are connected in parallel to the terminals of the ignition switch. It is in this place that it is most convenient to connect the entire system.

How to install an alarm with your own hands

Installing the device will not be difficult for people who are a little familiar with electrics. You will need a curved screwdriver, self-tapping screws, electrical tape, side cutters, a socket wrench, plastic clamps, a soldering iron, and a corrugated tube. Using this example, we will look at how to set the Magikar 5 alarm to autostart.

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First of all, remove the steering casing, as well as the decorative part of the center console. Then remove the instrument panel. It is there, behind the dashboard, that the alarm units are installed. You should also remove the pistons that secure the carpets near the handle that opens the hood. Next, take out the wires, which can often be found in the left threshold.

In this bundle of wires you need to find the fuel pump wires, the door switch cord, turn signals, the door switches themselves, as well as the trunk.

The siren wires from the alarm, as well as the hood switch, are mounted under the hood. This is done through standard tires. It can be found to the left of the steering wheel. There, under the hood, a temperature sensor, a limit switch and a siren are placed.

Then connect the central locking. Can be connected in such a way as to simultaneously connect to the control button, as well as to the standard car alarm unit.

The control unit is installed behind the dashboard. The mass of the device is also located behind the dashboard.

Next is the tachometer. It is connected to the instrument panel. There is usually a black connector with an orange wire. You can also connect to the handbrake wire there. Then the door and trunk limit switches are connected to the gray connector in the dashboard.

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All that remains is to bypass the standard immobilizer, and also connect the central locking and direction indicator to the BCM unit. At this point, the installation procedure can be considered complete.

Programming

In cases where there is a need to increase the engine cranking time, it is necessary to reprogram the central alarm unit. The default time on most models is 0.7 seconds. But not everyone has the option of software zoom. To do this procedure, you need to refer to the installation instructions. It contains a description of all the functions, as well as how to enter programming mode.

In addition, to change the alarm settings, you need to connect the Valet button and LED indicator. It also wouldn't hurt to have a speaker instead of a bell so that all settings can be controlled. On cars, the whole procedure consists of alternately turning the ignition on and off. This action must be alternated with pressing the Valet button. By the number of flashes of the LED indicator, you determine which function settings you are in. This is how you can easily autostart a car with your own hands. The alarm connection diagram is always provided by the manufacturer.

Tamper resistance testing

Not everyone has the skills and necessary knowledge in the field of auto mechanics. This article will help you understand the useful functionality of connecting an alarm system with auto start. The material is aimed at people doing this for the first time and for experienced car enthusiasts to learn something new for themselves. How to connect? How to choose? How will everything work?

And what consequences can you expect? To overcome difficulties in an unfamiliar area, the material presented below will help.

Using a telephone - is it possible?

But what to do if the engine starting time is very long? A time relay must be used. But this is not always possible to implement, so it is quite reasonable to use a cellular network. In addition, this is relevant for systems that are located at a considerable distance. Even if you are in another region, it is possible to start a generator, for example, in a greenhouse, to provide heating. But you need to adhere to some requirements, which will be discussed below. Autostart must correspond to them. It’s not difficult to do everything with your own hands. You will also need to change the design of the phone used as the autostart tool.

System requirements

The most important thing is to limit the circle of people who can call the phone used in the autostart system. You need to prohibit receiving messages and calls from all subscribers except one - the number that you plan to use for management. Even the “don’t tell anyone the number” option won’t help, since it could have been used by someone before. And you don't want your car engine or generator to start on false commands.

It’s not very difficult to do GSM autostart with your own hands. It will be more difficult to secure the mobile number used in the system from outside calls. But this can be done by contacting your mobile operator. It is worth noting that the diagram may differ depending on what model of car or generator you plan to drive. It all depends on the complexity of the ignition system.

Autostarting your car is as easy as shelling pears!

» Catalog of circuit diagrams » For a car

It all started with the fact that every morning I went out to my car, got into it, started it and sat there waiting for it to warm up. My car is old, carburetor, so for the first few minutes I have to sit and press the gas pedal... I have a car alarm with feedback and one button is not used, namely the “open” button. trunk,” and it was decided to attach the autostart to this button. Without further ado, let's move on to the circuit; it is not complicated and is assembled on an AVR ATtiny2313 microcontroller; the only difficulty for some will be to flash it. I note that when flashing the MK, you do not need to set the fuses; the proteus project is located below in the archive. The autorun diagram is shown in the figure below:

The circuit works as follows: in order to activate the circuit, a signal is sent to the 18th leg of the microcontroller, or we simply close this leg to the ground. Pin 18 needs to be connected with a free alarm output, in my case this is trunk opening. I connected it through a 300 Ohm resistor so as not to burn the MK port, 0.2V appears at the alarm output when it is triggered, study the diagram of your alarm for connection. If you have 12 volts at the alarm output, then you need to connect it through a relay. The circuit does not show a 5 volt “crank” (78L05 or LM7805) to power the microcontroller; all relays in the circuit are 12 volt.

After a signal is sent to the 18th leg of the MK, the “ignition” relay is turned on. After a few seconds, the “starter” relay and the “gas” relay turn on almost simultaneously (more precisely, after the starter relay, a second later the gas relay turns on and the car starts). After 7 minutes, the “gas” relay will turn off - during this time the engine will warm up and begin to hold speed, and after another 5 minutes the engine will turn off. To prevent the engine from stalling, you need to insert the key into the ignition switch within 12 minutes and turn it to the first position. The throttle relay is connected to a solenoid or similar element that will pull the throttle cable a certain length to the desired engine speed (this is necessary for carburetor cars; with injectors everything is much simpler and there is no need for a throttle relay). The printed circuit board was not developed, assembled on a breadboard. By the way, the relay for the starter should be set to 25-30 amperes, depending on the make of the car (depending on whether your car has an intermediate relay for the starter or not). We MUST take the wires of the appropriate thickness, otherwise the wire may become exposed, which may result in a car fire. A video of the device in operation can be seen in the video below:

You can download the project files (~130kb) from this link.

How to connect the circuit?

To do autostart from your phone yourself, you need to consider many factors. And don’t neglect to block all numbers except one. But the signal to start the process of cranking the starter is best taken from the speaker, which plays a melody when a call arrives. When you call this phone, voltage appears on the contacts connected to the speaker. Now it needs to be directed in the right direction - to the control system.

If the signal level is low (and it is), you need to use a simple field-effect transistor amplifier circuit. If desired, you can even install an amplification driver - a Darlington assembly. This is a small microcircuit that will increase the signal power several times. But it requires additional power, just like the telephone. You need the battery to last as long as possible, for this reason you need to connect the power from the car’s on-board power supply.

A set of important requirements

The immobilizer bypass module housing is usually made of plastic. And this is not accidental. Such a module is placed away from metal so that it does not block itself with its interference. Another thing is interesting: the image of the module, if it is installed, is usually not shown in any photo report.

Having connected the signaling, program any option and then remove the battery terminal. If the settings go wrong, most likely the main unit needs repair. The video at the end shows something else. It shows how easy it is to hack an alarm. Based on this information, do not make selection mistakes.

Precautionary measures

To ensure your safety, you should make it a habit not to leave your vehicle at speed. Otherwise, the autostart, assembled with your own hands, will start the engine, the car will start moving, since the gear is engaged. It is better to have a good handbrake, but it is not recommended to use it in winter. In addition, please note that you must block all incoming calls. This measure was discussed in detail above. All electrical networks must be protected with fuses.

All power circuits of the electromagnetic relay windings must be connected to the battery only through fusible links. This will prevent a fire if a short circuit occurs. However, if you use a car alarm, all protection devices are included in the installation kit. It is also worth noting that starting the engine yourself using an alarm with feedback is the most reliable and reliable option. And the cost will not be too expensive.

How does the alarm work?

Most modern cars are equipped with an anti-theft device called an immobilizer. Thus, a small chip with a stitched code is sealed in the ignition key. During ignition cocking, information is read from the key and transmitted to the computer. If the code matches, the car starts. If the code does not correspond to the specified one or is missing altogether, you will not be able to move. This means that remotely, when you press the button, the chip is not counted and the key will not work. How then does the car alarm system work?

The immobilizer will have to be bypassed; for this, a special electronic device is used in which an encoded chip is mounted. After these steps, the immobilizer bypass is installed between the car's engine control controller and the alarm unit.

Now, if you send a signal remotely, the alarm unit receives it, processes it and sends it to the engine control unit of the car. The lineman is triggered, and the system thinks that the key is in the ignition. The main thing is to correctly determine the connection points during installation.

conclusions

There are a lot of autostart control systems, but choosing the one that is ideal is quite difficult. Try to analyze the costs of different designs. A do-it-yourself engine auto-start module can contain either an alarm system or a cell phone. The last option turns out to be the most suitable. Especially if you have an unnecessary phone that can receive calls.

The only costs are the purchase of relays, wires and a SIM card. But there will be much less hassle with the alarm, since in this case it is used for its intended purpose. The only thing that needs to be done is reprogramming. And this is not always necessary, since usually the time of closing the contacts of the second channel is enough to ignite the air-fuel mixture in the combustion chambers. And the engine starts in less than one second. In some cases, the time increases to three. It’s easier to autostart the generator yourself, but you’ll have to carefully study the connection diagram to avoid mistakes during installation.

What is an auto alarm?

Almost every vehicle owner tries to make his life on the road more comfortable by equipping it, from mechanics to appearance, with all kinds of popular electronics. An advantage to the functionality can be such a convenient thing for a car enthusiast as an alarm system with auto start.

An alarm system with auto start is primarily an anti-theft system capable of starting the engine and car systems either using a key at a distance of 800 meters without objects interfering with the signal, or by setting a timer.

Connecting the system is convenient when it is sunny in order to return to a cool interior or when it is cold to a car already heated to a warm temperature.

Alarm systems with automatic start are divided into several groups: