Learning About Locksmith Tools and Services

New Car Buyer's Guide To Engine Control Unit And Smart Key Funciton

If you are in the process of buying your first new car, then you must be wondering about smart keys and exactly how they work. The good news is that smart keys and engine control units are both simple devices that are easy to understand, even if you are not a technology geek.

Engine Control Unit and Smart Keys

Most cars that were built in the last twenty years contain a part known as an engine control unit (ECU). The ECU in your new car immobilizes the car until a special key that contains a password is placed into the ignition. These keys are known as smart keys or transponder keys. If the ECU does not receive the correct alphanumeric password from the correct smart key, then the engine refuses to start.

Here is an outline of exactly how the steps of this process will work in your new car:

  1. you put your key in the ignition
  2. the ignition sends an electrical message to start the car
  3. the ECU asks the smart key for its password
  4. if the password matches, the car starts
  5. if the password doesn't match, the car will not start

Smart key systems have some advantages and disadvantages over typical lock and key systems.

Advantage of Smart Keys

The biggest advantage of smart keys is that they add an additional layer of security for your vehicle. Gone are the days when a criminal could simply open your car door with a piece of metal and then hot-wire start your car. Without the correct transponder key, your car isn't going to go anywhere for anyone.

Disadvantage of Smart Keys

The biggest disadvantage with transponder systems is that a replacement car key is no longer as cheap and simple as a trip to your local hardware store to have a key blank cut. Getting a new smart key involves purchasing a specific key blank, having it professionally cut, and then having the password programmed on to the memory located on the key. This process requires specialized computer equipment and is typically a fairly pricey process.


As a new car purchaser, it is important that you understand how each part of your vehicle functions. By understanding how your car's smart keys work, you will be better equipped when you need to have duplicate keys made in the future. If you have any questions about how smart keys work, then you should consult with a professional locksmith, like The Lock Shop, in your hometown. 

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Learning About Locksmith Tools and Services

Hi, my name is Yonni Pluthers. Several months after my daughter was born, the fire alarm in our new apartment started going off. Since it was a building alarm, we all had to immediately evacuate and wait for the fire department to clear the structure. I rushed out of the apartment with my daughter in my arms and closed the door behind me. Unfortunately, the knob lock was activated and I did not have my keys. Upon returning to my home, I found my door firmly locked. I called a locksmith and waited for her outside. I watched in awe as she wriggled the lock open using an incredible set of tools. From that point on, I developed an interest in locksmith services. I would like to share the tools and techniques used by locksmiths to open doors. I will also talk about locksmith services for vehicles on this site.