Key Fob Replacement and Reprogramming - Why Your Car Won't Start

Today, the majority of vehicles are equipped with an engine immobilizer in order to protect against theft of cars. If your vehicle will not start after inserting your key fob it could be a problem with a transponder which isn't sending a security signal to the immobiliser.

This is a quick fix that any auto locksmith on the Gold Coast can do. Let's examine the different components of your vehicle's immobiliser and find out what you can do.

Battery

It is essential to focus on the revenue and cost-savings opportunities of your auto repair shop. One way to do this is to offer key fob replacement and reprogramming to your customers. This will not only benefit your customers but also increase your shop's profits, without having to sublet to the dealership.

The key fob battery is used to power the remote locking and opening systems. The immobiliser is not powered by the key fob battery. The immobiliser is powered by a transponder located in the key, fob or instrument cluster. The chip transmits a passcode from the key or fob to the immobilizer unit of the car, which can be integrated into the PCM (power control module) or BCM (brake control module for brake control), instrument clusters smart junction boxes or standalone modules. The system then validates the code to make sure it is correct. If it's not it is, the system will shut down parts that are essential to start the vehicle, like the ignition or starter motor. This will make the vehicle difficult to start without the right key.

The immobiliser has proven highly effective in decreasing car theft since its introduction. Yet the thieves are always looking for ways to circumvent these security measures. One of these techniques is a recent trend called the Kia Challenge on TikTok that demonstrated how easy it is to connect a vehicle with hot wires.

The majority of insurance companies now factor in the use of an immobiliser when calculating premiums, making it even more appealing to purchase a car that already has this feature. Even vehicles that are factory-fitted with an immobiliser may have problems. Fortunately, these problems are usually simple and inexpensive to fix. Most times an immobiliser that is not working properly is the result of a dead or dying key fob battery. A quick diagnostic test could reveal this issue. If the issue persists it could be due to other reasons for the car's irregular behavior, such as electrical issues or a wiring issue. If this is the case, it's best to seek out a professional to diagnose and repair the problem.

Transponder Chip

In cars manufactured after 1995, a small electronic chip referred to transponder is integrated into the head of your car key. Also referred to as a 'chip key or a 'transmitter & responder key, it is created to stop the engine from starting if a third party has an exact copy of your car key. It works by sending a radio frequency from the key to your immobiliser system. If the code stored in the car's computer is in line with the signal sent by the key the immobiliser will be deactivated and the engine will be able to start.

The key with the transponder chip can be referred to as a 'fob' or a "smart" key because it is more difficult to duplicate than a conventional mechanical key. It is possible to duplicate a traditional key, motor but not a transponder one. In contrast to the remote central locking element of a standard key that relies on battery power, a transponder chip is powered by the infrared (IR) signal transmitted by the antenna ring that is located on the ignition cylinder.

To activate the transponder chip, the ignition cylinder must be turned on. The ring emits a burst IR energy which is received by a microchip within the key. The chip responds by sending a unique code to the immobiliser in your car. The car's computer examines the code in its memory to the one on the transponder and If the two codes are identical it will begin the engine.

If the immobiliser detects an unauthorised transponder or key is in use it will shut down the engine and prevent any of its essential components from functioning. Without a functioning engine the car will not be able to move, and it will be easy for a criminal to hot-wire the vehicle and then drive away. This is a powerful deterrent against criminals and is one of the main reasons why it is essential to get your car's key immobiliser repaired immediately you discover an issue. If you don't, the security light on your car will keep flashing and it will be impossible to start your engine.

Security Light

The immobiliser is powered by a small battery that transmits an electrical signal to the transponder chip in your key. This anti-theft device stops anyone from starting the car if they don't have the correct keys repair. If the system cannot identify a digital serial number from the chip in your key, it will disable the engine immobiliser and prevent the car from beginning.

The car immobiliser is a fantastic way to deter thieves, however it can sometimes be out of the sync. This could be due interference or the system is too sensitive. This may need an adjustment. To do this, just disconnect the battery. After 15 minutes, reconnect the battery and restart the car. This will reset the key system so that it is ready to accept keys once more.

The security light is an immobiliser's way of warning you of the presence of a problem. If the light is illuminated and you try to start your car, it is a sign that the code stored in the ECU does not match the chip on the key. This can happen if your car key has been replaced by a new key that's not compatible with the vehicle, motor or if the ECU was swapped in a wrong manner.

If this is the case then you need to go to a professional for assistance and get the transponder or key chip properly programmed to your vehicle. It's possible that your system isn't able to accept the key due to a software upgrade or bug. To test this, insert your key in the ignition and turn it to the ON position. Do not try to start the vehicle. The key should remain in this position for ten minutes. This should cause the security lights to light up and then to turn off. If it doesn't then you'll have to repeat the process and wait another 10 minutes. Repeat the process three times, and the issue should be solved.

Programming

The car immobiliser blocks the engine from running when a key or fob is not programmed correctly. It makes use of a unique RFID micro-chip that can't be copied and has its own digital serial number. The immobiliser will stop working in the event that it is unable to recognize the code. It's hard to beat.

Modern cars are fitted with this security system in the standard configuration. This makes it difficult to hot-wire a car or utilize a different key for starter. The system operates by sending a passcode from the key fob to the ECU. The ECU then knows that it's the correct key and that the passcode hasn't been compromised. The system will not allow the vehicle to start if it doesn't have the correct code. Some models will even notify the owner in the event that someone attempts to use an incorrect fob or key.

The system isn't 100% secure, however. Some thieves have gotten around the immobiliser by using techniques such as 'hot wiring.' This involves crossing the wrong wires in the wiring of a vehicle, which fools the ECU into thinking that the correct key or fob is being used. But, this technique is quite risky and requires a great deal of knowledge of how to carry out the procedure without cutting yourself. Modern car thieves are employing more sophisticated methods, for instance, Bluetooth or other specialized apps to steal a car's information and remotely control it.

Car owners will often get warning lights that signal that the immobiliser has gone off the rails. This can occur for various reasons however the most common reason is a defective battery in the keyfob. A simple replacement can fix this problem.

If this does not work, it could be that the transponder chip is faulty or the ECU is not matched. It is more difficult to fix and diagnose because it requires a specialist car locksmith or dealership. However, a car immobiliser can also be damaged due to water intrusion, or even being removed from the fob or key. If you experience any of these issues it is a great idea to visit an auto dealer in your area or garage to seek help.