How Car Key Chip Works?

How Car Key Chip Works?

A car key chip provides extra security to your car similar to a credit card.

How does the car key chip works? A small computer chip is placed inside your key, and it authenticates the original and duplicate car keys by replying correctly to the Engine Control Unit (ECU) from the car engine.

ECU will send a coded message to the key when you plug the transponder key into the ignition. Remote keys are the need of the time. You want to protect your car from theft.

In this article, we will discuss how car key chip work? How it provides and increases security. Why are remote keys more expensive than expected? Why car dealers charge extra for remote keys. 

What is a Transponder Key?

Cars manufactured after 1995 have transponder keys as a part of their security measures. Remote keys are also in practice for homes, garage doors, and gates. Transponder key transmits a low-level signal, a receiver reads these signals.

A microchip is allotted a unique serial number. The receiver needs a correct serial number to open or unlock the car. Transponder keys are often used for home security systems and car locks. When the key is inserted in the car, the signal is transmitted to the receiver that is located near the ignition. If the serial number matches the number programmed in a car it will start when the driver turns the key. 

How Does Car Key Chip Work?

A transponder key contains a microchip, and the chip is assigned a unique serial number. This serial number is also known as a unique digital identity code. This code is set during the initial programming at the time of key making.

When someone wants to open or start a car, he/she presses the transponder key, and a microchip that is present inside a key sends code to the car. The engine of a car verifies the code and start the engine.

If the car wasn’t able to validate the code, it would remain immobilized and locked. So, we can say when the code sent to engine matches and then it will start the car. Otherwise, it won’t accept the code and unlock the car and engine. 

Advantages of Transponder Keys

  • It is the most secure lock system for a vehicle. 
  • Duplication of the transponder key is almost difficult. 
  • Keys can be used only to unlock doors and windows.
  • If someone succeeds in opening the car door, still the engine won’t start. 

Disadvantages of Transponder Keys

  • The replacement of these keys is expensive. 
  • The range of transponder key frequency is limited. 
  • For using the transponder key, you will have to be closer to your car. 
  • If someone doesn’t have an original transponder key, they can still open your car doors and windows. 
  • When you lose the original transponder key, you can’t start your car, and you will have to contact your car dealer. 

Why Are Transponder Keys More Secure?

These keys provide security for your vehicles in two ways. They prevent car theft by rendering hot wiring. When the car doesn’t detect the same serial number, it won’t start.

Transponder keys are different than the traditional ignition key, and they contain a unique digital virtual ID. Transponder keys use a unique ID, so there is no chance to use someone else’s key in your car. Unfortunately, criminals have found ways to break into cars even with transponder key security, 

How to Get a Copy of Transponder Key?

It’s not always clear from where to get your transponder key if it’s lost, has stopped working, or stolen. You need to ask a trusted locksmith whether you need to have a new key programmed. A locksmith can help with remote keys, and they use the same equipment that car dealers use to replace transponder keys. They are trained and can provide a perfectly same and functional copy at much less price than a car dealer. 

Why Is Replacement of Car Transponder Key Expensive?

It is inexpensive to get a replacement for the traditional key. However, when you get a replacement of a microchipped key, prepare yourself for the price of a new key because car dealers charge the price of a new transponder key, and it is much higher than the expectations of a person.

Microchip keys are expensive for everyone to purchase, including dealerships and locksmiths. Programming such keys require special skills and equipment. If the key doesn’t contain a microchip, you can open a door or window, but you can’t start an engine.

Which Companies Are Using Transponder Keys? 

Top-notch car manufacturers like Toyota, Ford, Nissan, BMW, and Chevrolet are using transponder keys. These keys were tested in all German and non-German models by 1998. The concept of this key was to reduce car theft cases. Before the concept of transponder key, cars were stolen by using duplicate keys. 

How to Program Chip Key?  

Transponder key offers a level of security and convenience for your car. If your car is equipped with a key chip system, you need a programmed key for turning on the ignition system. You can program or reprogram the key in just a few minutes. 

  • Insert the chip key into the ignition of your vehicle and turn the key to ‘on’ position.
  • Leave the chip key in “on” position for ten and a half minutes and then turns it off.  
  • Repeat both steps three times and turn off the key after the third time.
  • Turn the key back to the “on” position, and it will complete the programming sequence. Now, your chip key is ready to start your car. 


Technology is evolving day by day, and it is changing lives. Key chip is also one of the examples of technology and programming. It helps to make your car secure and enhances security. A transponder key contains a chip with a specific identity number. When this number matches the number provided to the engine, then the engine gets started. Some duplicate keys can only open the doors and windows, but can’t help to start an engine.  

Efforts have been made to get the information as accurate and updated as possible. If you found any incorrect information with credible source, please send it via the contact us form
Author: Sky Hoon
He loved the future of self driving car and cannot wait for one. In the meantime, he loved to read up all about car and components like a computer.
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