What is immobilizer? Why immobilizer is mandatory in latest cars?

 

What Is Immobilizer? Do Immobilizer protects your car from Thieves?

necessity of immobilizer for vehicles

Immobilizer is known as anti theft system or an immobilizer acts like an anti theft device in a modern car or vehicle. Today immobilizer is a basic need and compulsory for every car and vehicle on the road. The immobilizer prevents a car from being theft by thieves who are normally interconnecting wires to start and thieve a vehicle. An immobilizer is connected to the car battery all the time and it is active regardless of the key is there in the car or not. Also it is working automatically without the intervention of a car driver. The immobilizer recognizes the car key electronically and it allows the car engine if a pre-registered key had been inserted in the car's ignition cylinder. Modern immobilizers are considered as reliable anti theft devices for car security and protection.

Function of immobilizer in car

The immobilizer in a car or vehicle disables the mobility or starting system of your car or vehicle. Immobilizer cuts off the fuel or ignition or in some models both to the car engine to prevents it from starting if original registered key is not inserted in the car key cylinder. The immobilizer cuts of fuel or ignition by commanding the car ecu. As in modern cars and vehicles the fuel injection system and the ignition system is directly commanded from the engine management computer or engine control unit or ecu. Some people do think the immobilizer would command an out side relay which controls the fuel and ignition, Bypassing that relay could make the car engine start. This is not the case in reality. The car manufacturers are not giving that easy time to thieves. They make their immobilizer system is very complex way that an average thief can't break into it. Modern immobilizer systems uses proximity transponder key system. In such transponder key system there is a transponder located in the key head. There is no battery required to power up the transponder. The transponder receives its power from the burst of the ignition cylinder coil. The coil is in a shape of ring around the key cylinder which is connected to the immobilizer key amplifier. The amplifier performs two tasks. It provides power burst to the coil which is used to power up the transponder inside the car key. The second task of the key amplifier is to receive the code from the key transponder and amplify that code and send it to the immobilizer for comparison. In the immobilizer the received code is compared to a pre-resisted code. If the code matches, the immobilizer sends command to the ecu or pcm to allow the engine to start by allowing fuel or ignition or both to the engine. It the code don't match, the immobilizer would not send the command to the ecu and the ecu wouldn't allow to start the engine by cutting of the fuel or ignition or both. The immobilizer is communicating the ecu by some data communication not the simple voltage level which could be bypassed.

What is transponder key

In normal situations the thieves break into car and they hard wire the ignition wires under the steering column at ignition cylinder. In older days or in local fitted cng cars the engine gets started with this attempt. But the modern cars with immobilizer facility this starting attempt would simply not work. The hard wiring wouldn't allow the fuel and ignition to start the car. There is off course way of new key registration in the ecu to let the car started but that is not an easy way. That needs to register a new key in immobilizer to have special key coding or key programming equipment or key programming computer and a lot of skill to accomplish the job. Also many car manufacturer have adapted they procedures to program the key in such a way that those procedures do need half to one hour time to register the key in the immobilizer. That time delay is specially created so that the thieve have no such big time to program or resister a new key in the immobilize to steel the car easily. These all security features makes the immobilizer a very effective and efficient way of protection a car from stealth. In new modern cars the immobilizer is a compulsory and mandatory part of a car or road vehicle whereas in older cars immobilizers can be applied and can be added as add on security feature.

Transponder Key amplifier and antenna for immobilizer

Is immobilizer good or bad for a car?

As immobilizer is a great safety and security feature for a car. Although it has some difficulties and vulnerabilities too. Immobilizer is an extra and complex equipment. Adding an extra equipment to the car and especially something which prevents a car from starting in case of any abnormality, is sometimes very big trouble and cumbersome. This is in case when there is everything OK and you have original key and the car refuse to start due to the malfunction of an immobilizer. Such a problem wouldn't come in cars without immobilizer.

But on the other hand as the worst case situation of car theft is handled by the use of immobilizer, an immobilizer is mandatory to be installed in all modern cars.