What Is Immobilizer: How Reliable is it for Your Car’s Security?

Immobilizer feature

An immobilizer is an anti-theft device, which is found in most modern cars. As a matter of fact, in countries like Germany and UK, an immobilizer is mandatory in all cars. This device prevents thieves from hot wiring the car. An immobilizer works automatically and doesn’t need the owner of the car to activate it. Immobilizers are considered to be effective anti-theft devices.

car immobilizer

How does an immobilizer work?

An immobilizer disables one of the systems which start a car’s engine. It usually disables the fuel supply or the ignition. There are two components involved; the transponder in the ignition key and a radio frequency reader. The radio frequency reader is found in the steering column. When the ignition key is placed, the transponder sends a unique identification code to the frequency reader. If the code is correct, the car’s computer control allows the ignition system or fuel system to start the car. If the code is incorrect or not present, the computer control disables the ignition or fuel system of the car and it will be unable to start unless the right key is used.

immobilizer key

The most common way a thief steels a car is by hot wiring it. Hot wiring involves breaking the steering column and connecting the ignition wires of the car. With the immobilizer, the car won’t start even if the wires are connected, because the system deactivates the ignition. Immobilizers are very effective and have become a standard in most new cars. They can be installed on older cars as well.

immobizer key

How good is it for your car?

An advantage of the immobilizer is that it doesn’t need to be activated by the car owner. It works automatically and the car’s computer control detects any wrong code and absence of a key. However, immobilizers have some vulnerabilities. Many immobilizers in cars use the Megamos-chip, which can be crack-able. It’s faster to program a new key than to try to duplicate an existing key, especially in modern cars.

Immobilizer is a very important device and it’s mandatory for a car to have an immobilizer in many European countries. In a recent study, immobilizers have reduced the overall rate of car theft worldwide. According to the study, car theft has been reduce by 40% between 1995 and 2008.

Samiullah Sharief

Samiullah Sharief is a car enthusiat. He is passionate about writing blogs and reviews about cars. His hobbies are driving,watching TV Shows like Top Gear, Mega Factories and he follows Popular car magazines. You can reach out to him by tweeting @sami649

  • Zulfiqar Ali Soomro

    My car (baleno) was once saved from being stolen thanks to its immobiliser.

  • Samiullah Sharief

    immobilizers should become mandatory for cars in pakistan..

  • Guest

    “…a thief steels a car…”

    ROFL. Paradoxical … no?

    The article falls short on information. There are multiple generations of immobilizers, and the immobilizer of one car can be more effective compared to another one depending on which generation it belongs to.

  • KaKa

    Does Vitz 2nd Gen. has immobilizer pre-installed?

  • German Ab

    What to do with an extra plain key with my Daihatsu Move? but there is no key socket/place in the doors.

  • USInfidelPorkEater

    Immobilizers are very good for keeping a perfectly drivable car from starting for the owner. Then the owner can get learned in the high cost of this very unnecessary feature on his car. This works well for the auto manufacturers and repair shop not so good for the vehicle owner. I have experienced this personally and I would rather my car be capable of being stolen and starting rather than deal with the aggravation of a no start because of a malfunction of the immobilizer circuitry and resulting repair and reprogramming costs. No thanks.

  • DrNauman Sheikh

    Mr Samiullah please can u elaborate more on how immobilizers are vulnerable? and are the immobilizers used in our country possess the same Megamos-chip, which can be crack-able? if yes what can we do to sort this problem?

  • Tanzeel Mohsin

    Immobilizer keys can be re made also – it requires a programming kit (kind of a handheld device) – The thing is usually a thief that would be stealing your car would be in a hurry so he would somehow open the door get in and start your car by bypassing starter switch as mentioned in artilcle.
    However cars with immobilizer don’t start that way – the thief would basically have to first rip through your door poshish and get the lock out – then make a key that can be inserted into ignition – once he is done that – he will also require a kit that programs immobilizer keys and that would be connected to OBD port of your car – once he has that kit ready (kind of a device) and key inserted into ignition, the computer will code the key and car would start but this takes around 20 minutes minimum so a thief can steal plenty of other cars in that time – why go though the hassle? So yeah immobilizer doesn’t gurantee ur car safety but it makes stealing difficult for the theif!

Top