Useful Facts about Modern Car Keys – Part I

You may know about chip or transponder car keys; but you may not know what exactly they are and how they work. So, anytime if you have to make a copy of your car key, you may be surprised with its high cost and wonder why it is so. In this very first part of the article, we explain about the 2 types of car keys of today.

Most car keys fall into 2 basic types:

  1. Transponder keys
  2. Non-transponder keys (This is also called Flat Metal Keys)

Remember first not to confuse automotive remotes with transponder (chip). Remotes can only lock and unlock your car. Of course, there are some remotes which are built inside the keys (remote head keys), but others are not and are separate (fobs). The latter operate independent of the transponder security system.

In case of the flat metal key (non-transponder), the key is single- or double-sided, and works exclusively with the mechanical cuts. When the various sized cuts on the key fit in the various sized tumblers inside the lock, the key turns.

Transponder key on the other hand is a part of the antitheft system of the car. The word ‘transponder’ is a combination of ‘transmitter + responder’. It’s a small microchip set within the plastic head of your vehicle’s key and gets a signal from an antenna ring placed around the ignition cylinder of your car. The computer in the vehicle should receive the correct response from the transponder key; otherwise the computer won’t let your vehicle start.

New challenge and password transponder systems make use of an encryption with something called rolling code (because of rolling code system, the challenge and password change every time after used). It can be thought of as a complex mathematical algorithm in which the automotive transmits a six digit number (anything from 0 to 999,999) and the transponder is designed to crunch the figure and respond. For example, say the key is turned in the ignition and a random number 7 is transmitted by the car within a fraction of a second, and the car is aware of the algorithm “What’s X plus 3 – 1”. If the key is programmed correctly, it will crunch the numbers as soon as it receives the challenge (7).

7 plus 3 – 1 = 9; so, if the Transponder returns the number 9, the car understands that the driver is using a correct key.

There are other systems which are more simplified which make use of chip keys having an identification number that is to be recognized by the car. It works along the lines of an ATM pin number. An example of this system is GM’s VATS or Vehicle Anti Theft System keys. A VATS key has a resistor having 1 among 15 preset resistances. If a key is created with proper cuts and turns in the cylinder, it should still get the proper resistance or else the car will shut down, and even a correct key won’t be able to start it. Such a lockout often lasts for 3-4 minutes.

You may wonder why automakers use transponders. It is said that back in the 90s they were confronted by the car insurance providers whose data revealed that if the automakers didn’t take proper measures about the rate of theft, the insurance providers would not be able any longer to insure new cars at a reasonable rate. Irrespective of whether this story is true or not, transponders will stay henceforth. Every automaker in the US has one model at least using transponder keys. Even some motorcycles use them.

All in all, using a locksmith is advisable for making a copy of your car key as locksmiths have the expertise and equipment needed for this.

More on this topic in the next parts of this article. Visit Portland Locksmith Pros to know more about cheap car key replacement in Portland who provide prompt service at your site and is available at any hour of the day.

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