What You Need To Know About Car Key Programming

As car keys and fobs become more advanced, so does the technology that allows them to work properly. In today’s automotive world, making a car key is much more complex than cutting it into the right shape. As such, car key programming is an invaluable service that automotive locksmiths can provide for their clients.

Knowing your way around the different car key programming methods and tools will help you serve clients who need to program spare keys or replace a broken or lost key. Learn how to offer this service at your automotive garage or locksmithing business with this rundown of what you need to know about car key programming.

How Programmed Keys Work

Before you learn about the different methods for programming car keys, you must first have a clear understanding of how modern automotive keys work. Each key and fob uses a transponder chip to connect to and operate a vehicle. This transponder chip holds data that corresponds to the car—think of it like a password coded into the inside of the key fob.

The vehicle requires a specific password to work. When the key or fob is within range, it sends the password from the transponder chip to the car. If the password matches what the car’s programming is looking for, then the key works and the car can operate. This is what allows cars with keyless entry or push-button starts to function. If the password doesn’t match the car’s system, then the car won’t unlock or turn on, and the key is useless for that vehicle.

Different Programming Methods

There are several different ways to program a car key, but they all work in essentially the same way. Car keys and fobs already come with transponder chips inside. The goal of programming a key is to rewrite the data on the transponder chip to hold the specific password that your vehicle needs in order to operate. To do this, the programmer must obtain the correct password from the vehicle, then write that data onto the transponder chip in the new key. However, the act of obtaining the correct password can differ from vehicle to vehicle. This is where the different programming methods come in.

Onboard Programming

Onboard programming is the simplest and fastest method of key programming; anyone can do it in a matter of minutes regardless of their level of experience or automotive knowledge. However, onboard programming only works with vehicles that have existing onboard programming systems—such as newer General Motors vehicles. You also need a spare working key to perform the onboard programming procedure—some makes and models even require two working keys for the programming process to work. As a result, this method is only useful if you want to program a spare key for the vehicle.

Before programming the new key through onboard programming, make sure you have a programmed spare key (or keys) on hand, as well as the new key you want to rewrite. Start by inserting the already programmed key into the ignition and turning it to the On position; you want to start the car’s electrical system without starting the engine. Next, turn the key to the Off position and remove the key. Quickly insert the second already programmed key (if applicable) and repeat the process. You want to insert the next key within five seconds of removing the first key.

Once you have done this with both programmed keys, quickly insert the new key and turn it to the On position. Again, you want to insert this key within five seconds of removing the last one. If the programming is successful, the security light in the vehicle will turn on.

OBD2 Programming

Not every vehicle comes with an onboard programming system. In these cases, retrieving the correct transponder chip password from the vehicle is a more complicated process that requires a trained automotive locksmith who has access to advanced programming devices.

OBD2 programming involves using the onboard diagnostics system to obtain and modify the data for the key or fob. To do this, an automotive locksmith uses an OBD2 interface, also known as a service plug, to convert signals from the vehicle’s onboard computer into information that the system can understand. The programmer can then use this information to rewrite the code on the transponder chip and successfully program the car key.

This programming method requires expensive, highly technical equipment as well as extensive knowledge of how to operate the OBD2 interface. That’s why it’s important for automotive locksmiths to have the right equipment and experience to help clients who need OBD2 programming.

EEPROM Programming

Like OBD2 programming, EEPROM programming is a complex procedure that requires specialized equipment and in-depth knowledge of the vehicle’s computer systems. EEPROM stands for Electrically Erasable Programmable Read-Only Memory. This method revolves around the microcontrollers that contain memory for remote keyless systems, vehicle immobilizer systems, and other electronic devices within certain types of vehicles.

With EEPROM procedures, the programmer works with the circuit boards within the vehicle. The programmer will extract a copy of the key file from a microcontroller on one of the car’s circuit boards to obtain the correct password. Then, the programmer will use the vehicle’s programming mode to either clone a key from the file or add a key to the file.

This process requires extensive knowledge regarding circuit boards, electronics, and soldering; making a mistake during this process runs the risk of corrupting information in the vehicle’s programming. For this reason, it’s imperative to work with an experienced automotive locksmith for this procedure.

How Long Car Key Programming Can Take

When a client needs a new key for their vehicle, one of the first things they’ll ask is how long the procedure will take. As with many other things, the answer changes from client to client. Onboard programming is a straightforward process that takes a matter of minutes. OBD2 programming may also take only a few minutes as you connect to the OBD2 port and program the key. However, for more complex procedures—like EEPROM programming—it might take a few days to safely obtain the vehicle’s password and write it onto the transponder chip.

The Right Tools for Your Automotive Locksmith Business

Learning everything you need to know about car key programming is only part of the process. You also need the right equipment to successfully program automotive keys and fobs for your clients. When you visit Locksmith Keyless, you can browse an extensive range of automotive devices, including key fob programming tools from leading brands in the industry. Find the tools and equipment you need to help keep clients and their vehicles safe and functional when you shop at Locksmith Keyless today.