Security systems are constantly moderniziriruyutsya. But the General principle of operation remains unchanged. Monitored several critical parameters, such as the position of the body and opening doors. By changing the position of the body the signal to the control unit, which converts it and sends a signal to the siren. Also receives the signal on the key FOB, if you have feedback.

Even the simplest car alarm has many features. For example, locking doors when ignition is turned on, closing the Windows when arming. All these functions can be switched on and off, to improve the operation of the car. Also sometimes you need to complete disconnection alarm. If you left for a while the car in service, you will need to completely disable absolutely all security functions.

Part of the automotive alarm

The basis is a Central unit, which produced the connection of sensors and actuators. Sensors:

• strike;
• volume;
• limit switches on the doors, the hood and trunk.


• drive electric Windows;
• Central lock actuator;
• siren.

You can still add the Valet button and led indicator. The latter is necessary to monitor the status of alarm, can be performed as individual LEDs and led matrix. But the Valet switch can be classified as input devices, as with it made the programming of the alarm functions.

But not only programming you can use. The main task is the translation of the security system in the so-called service mode, in which we disable all alarm functions. Also emergency shut-off can produce with it. For example, if you lost the firmware of the pendant, you will not be able to set the car for protection or to remove her. In this case you will need emergency shutdown.

How to find a treasured button?

If you set the service alarm, it is required to provide information about the button. The fact is that with it disabled the protection for a few seconds, so for thieves it is very valuable. And competent electrician will never set the button in a visible place, it will be in that place where only you will know.

This can not be said about car dealerships. They install alarm systems so often, particularly not worried about the location of the service button. She's usually in plain sight, covered only by the cover. Buying a car with an alarm, be sure to ask the seller about all the intricacies of the security system.

But to find a button you can own, you just find the Central unit. According to the instructions to see what's connected button. And from these insights unit is a thin wire to a small button.