Types and principle of operation of the immobilizer crawlers
Content
Almost all modern cars already from the assembly line are equipped with a standard immobilizer - a system for blocking the start of the engine when attempting to steal. It is a powerful and reliable anti-theft system, but sometimes it can interfere with the installation of advanced alarm systems. The immobilizer is associated with the key of the car in which the chip (transponder) is located, that is, the engine will not start without a registered key. You will need a lineman to use the remote engine start function to warm up or if you lose your keys.
Purpose and types of immobilizer crawlers
The main task of the lineman is to "deceive" the standard immobilizer so that it receives a signal and gives a command to start the engine. There are two types of immobilizer systems:
- RFID;
- VATS.
RFID works on the principle of a radio signal that comes from a chip. This signal is picked up by the antenna. This type of immobilizer is found in European and Asian cars.
The VATS systems use ignition keys with a resistor. The decoder senses a certain resistance from the resistor and unlocks the system. VATS is used primarily in America.
The easiest workaround
The key chip (transponder) emits a weak RF signal in the electromagnetic field of the ring antenna in the ignition lock. It is enough just to remove the chip and tie it to the antenna or hide the second key in the area of the ignition lock. This method is the simplest, but the functions of the immobilizer are lost. It becomes useless. You can start the car with a simple key, which plays into the hands of intruders. There is nothing left but to bypass the system in other ways.
RFID System Immobilizer Bypass
A standard immobilizer emulator is a small module that holds a key with a chip or the chip itself. This will require a second key. If not, you need to make a duplicate.
The module itself consists of a relay and an antenna. The relay, if necessary, restores or breaks the connection in order for the immobilizer to perform its functions. The module antenna is connected (wound) with the standard antenna around the ignition lock.
The power lead (usually red) connects to the battery or to the alarm power. The second wire (usually black) goes to ground. It is important that the autostart works from the alarm. Thus, the antenna of the device is in contact with the standard antenna, power and ground are connected. This is a common connection, but there may be other schemes.
Immobilizer bypass of the VATS system
As already mentioned, in the VATS system, there is a resistor with a certain resistance in the ignition key. To get around it, you need to know the value of this resistance (usually in the region of 390 - 11 800 ohms). Moreover, it is necessary to choose a similar resistor with an allowable error of 5%.
The idea of the bypass method is to connect a similar resistance instead of the one used in the key. One of the two VATS wires is cut. The resistor is connected to the alarm relay and to the second wire. Thus, the presence of a key is simulated. The alarm relay closes and opens the circuit, thereby bypassing the immobilizer. The engine starts.
Wireless Crawler
Since 2012, wireless bypass systems began to appear. No extra chip needed to bypass the system. The device emulates the transponder signal, reads it and receives it as the main one. On advanced models, additional installation and programming work may be required. Data is written first. And then there is a setting on special equipment.
The leading manufacturers of wireless bypass systems are:
- Fort;
- StarLine;
- OVERRIDE-ALL and others.
Some alarm models already have a built-in immobilizer emulator, since without it autostart and other remote functions will not work.
Some drivers prefer to simply remove the stock immo from the system. To do this, you may need qualified assistance from specialists in the service or skills in working with electrical equipment. Of course, this will reduce the security of the vehicle. Also, such actions can affect the operation of adjacent systems in an unpredictable way.
It is worth remembering that autostart to some extent makes the car vulnerable to intruders. Also, if the immobilizer crawler was installed independently, then the insurance company may refuse to pay compensation for theft of the car. Either way, setting up a crawler is a tricky operation that needs to be done wisely.
