Engine immobilisers keep your car safe. We find out how it works
In India, Marutis constitute the largest number of stolen vehicles. This could be because these cars can be disposed easily and also the fact that they are many in number. Therefore, hoping to reduce car thefts, all Marutis except the Gypsy and the Esteem are going to be fitted with an immobiliser.
Developed in the 1980s, the immobiliser system uses an authentication system which is integrated into the car’s computer (the ECU – electronic control unit, or EMS engine management system), which in turn cuts-off/gives power to the vehicle’s electronics. Pushed mainly by insurance companies, the immobiliser became compulsory in the United Kingdom in 1997 and Australia in 2001.
Since its inception, a number of systems have been tried and the one chosen has also been adopted by Maruti.
The system relies on Radio-Frequency Identification (RFID). A microcircuit embedded in the key contains the code and is activated by a small electromagnetic field which induces current to flow inside the key body.
This allows the key to send a digital code to the receiver (usually hidden in the barrel of the key slot) in the car.
Once the code is accepted by the car’s computer, it allows power to be given to various systems like the ignition, fuel pump etc. To prevent tampering, the frequency used is of low level, and external devices cannot pick it up. Rolling codes are also used to prevent duplication. Here the code gets changed with each use, and the spare key has a separate code.
Maruti has dubbed its system as iCATs (Intelligent Computerised Anti-Theft system) and had to redevelop its engine computers to integrate it. The company has even developed a version for use in the carburetted Omni LPG.
Older models and aftermarket options rely on visible receivers and electronic contact switches, which require the electronic key-fob to be touched to a contact mounted near the ignition.
Higher-end cars like the Porsche Cayenne SUV feature an even more convenient system, which does not require the key to leave your pocket. Instead, a dummy key is already in place in the ignition. Once you approach the car, the system detects the key on the person and unlocks the car. All you have to do is twist the dummy key, and the engine will come to life. If the key is too far, the immobiliser gets activated.
If your vehicle comes attached with this safety device remember to keep the key as safe as possible to avoid anyone driving away with your car as whoever has the key, has access to the car. Also, an immobiliser does not mean that no one can ever break into your car so always practice precaution regardless of how safe you think your car is. The norms governing immobilisers have already been framed and will come into place shortly. In fact, this type of security system is better than electronic locks. Car owners who have electronic locks should not be at ease thinking their vehicle is safe; these can be easily deactivated. What’s more, they are so vibration-sensitive that they often give out a false alarm, in the process create a big noise and turn off people. This defeats the purpose of the system.