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Key FOB Replacement

What is a Key Fob?

key fobA key fob is a security device used in automobiles and computers to provide hardware-based security. It is deceptively simple to look at and operate. Unless pointed out to them, a lot of people think that the black plastic handle attached to the key blade is just a plastic extension to hold the key blade. But equipped with electronics and some push buttons, it has evolved into a sophisticated extension of the owner, using rolling codes, a transmitter module, and sophisticated firmware to communicate with a receiver on the the vehicle. This black plastic thing that you hold in your hand has evolved from a simple alarm and immobilizer de-activator to a device that can remember your air conditioning and heater settings, seat adjustments, allows you to remotely start your car, has a panic mode for emergencies, and can even communicate tire pressure and fuel levels while outside the car.

The more sophisticated key fobs have done away with the need to insert a key in the doors, the trunk, or the ignition switch, which can be a great convenience.

Key Fob Types

The simplest key fob is the one with a key blade, a plastic handle, and a couple of buttons on it. Equipped with a battery and basic electronics, this type of key fob is used on entry level cars. Usually, the fob’s only function is to unlock the doors and disable the car’s alarm. The key is used in the traditional way for opening the doors and starting the car.

A step up to this basic fob is a transponder key. In addition to having door unlock and alarm functions, the transponder key contains electronics that pair it to a specific vehicle. Without the paired key, a hostile party may be able to open the vehicle doors but the car or truck will not start. This is because the immobilizer circuit will not have been deactivated without the correctly-paired transponder key. Theft prevented. Some variations of the transponder key have a remote start function.

The next step up from the transponder key is the fob that dispenses with the traditional key blade. This so-called proximity key unlocks the car when it gets within range. It also allows the driver to start the car (via a console-mounted push start button) as the immobilizer is also deactivated when the driver gets onto the seat. While very convenient, some usability issues have cropped up, such as your smart key traveling with another car after your car has been started. A few manufacturers have tried to sidestep this by requiring the driver to insert the smart key onto a slot in the dashboard.

Depending on the luxury options one has opted for, the more sophisticated key fobs offer remote start, driver seat preferences, climate control settings, GPS tracking for emergency services, tire pressure, and fuel levels. Even an odometer reading. Some Volvos even feature a heartbeat sensor. This innovation detects if you’ve left a child in your car, or if an intruder is already inside your vehicle.

As key fobs become a new symbol of status, manufacturers have begun to make these fobs aesthetically more pleasing, with gold trim and whatever styling cues are in fashion for the moment. This indeed sets them apart from the black plastic fobs network administrators use, but the basic function is still the same.

Key Fob Issues

As most of us have experienced, electronic stuff have varying degrees of reliability and sometimes stop working for seemingly no reason at all. The easiest way to kill an electronic circuit is to immerse it in liquid, but there are other ways which can affect your key fob to the point that it is useless.

Other ways a key fob may stop working include dead batteries, failed/corrupted circuits, radio interference, a worn key blade, or a broken door antenna on a keyless entry system. Battery failures can be from voltage drop, extreme temperature, leakage, or corroded contacts. Corrosion buildup between the battery and contact prongs can also induce enough resistance to diminish voltage by a significant margin.

Then too, there is the human element, where the user inadvertently locks the key inside the trunk, a smart key fob getting misplaced while driving (left on the convenience store counter, at the gas station, etc.), or having two smart key fobs for different vehicles inside the car.

Dead spots inside the car can also render smart key fobs partially or fully inoperable. This can result from interior panels being removed or antennas jarred loose from vibration. Radio interference from multiple electronic devices or proximity to radio towers has also been observed to affect the electronics in key fobs.

Unfortunately keyless entry systems can be hacked, and thousands of cases of theft attest to the insecurity of a system that is supposed to prevent theft. Early implementations of an insurance standard found that systems from Japanese manufacturers were more secure than German-made systems.

Key Fob Replacement

key fob replacementIf you find that you need to have your key fob replaced, there are a few options you can pursue. A dealer will use OEM replacement parts and will be able to service you if you bought your car new at the location. Unfortunately, going to the dealer is likely the most expensive option too. To note, a dealer surprisingly can mean inconsistent service quality as the person working on a key does not have as much experience with auto keys as a specialist would. Sometimes keys are done outside of the dealership and can mean a long wait time before getting your key repaired or replaced.

The Do-It-Yourself route is also a consideration. You can find replacement kits online or at auto parts stores. But since the electronics and handshaking between fob and vehicle are specific, you must ensure that you get the exact replacement. Otherwise, the replacement that you get may not work at all. Or you may get a replacement fob that may work for unlocking and starting the vehicle but fail at operating the other systems put in place by the manufacturer.

A qualified auto locksmith can provide fast, reliable service at a better price than a dealer can. Professional car key locksmiths have both the skill and specialized equipment to perform key fob replacement or repair. They stock hundreds of replacement fobs & keys to ensure that you get what you need for your vehicle. Professional auto locksmiths deal with broken, lost, and replacement key fobs for a living, so they are up to date with the technologies and skills required to replicate all kinds of keys and key fobs. More importantly, professional car locksmiths understand the gravity of a lost or broken key and are in the best position to respond immediately to your need.

Need assistance with a replacement key fob? Contact Chicago Car Keys today and get a new car key made quickly.


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