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What You Need to Know About Keyless Ignition Systems

They're Convenient but Potentially Dangerous

We're living in an age when convenience is king. And one automotive amenity that's gaining popularity is the keyless ignition system, also known by such names as keyless start, keyless push-button start, intelligent key and smart key. Whatever it's called, this feature allows you to fire up your car's engine without fumbling for a key in your pocket or purse.

Keyless ignition systems first began appearing on production cars in the late 1990s and early 2000s, and like many tech and convenience features, they were initially available only on luxury models and other high-end vehicles. The Mercedes-Benz S-Class is generally recognized as the first mass-produced car with keyless ignition, followed by models from Acura, Cadillac, Lexus and Rolls-Royce. Keyless ignition has become increasingly common in cars: In 2008, keyless ignition was standard on 11 percent of the vehicles sold in the U.S. By 2018, it was standard equipment on 62 percent of vehicles sold.

If you don't have it yet, how does keyless ignition work? Do you need it on your next vehicle? And, perhaps more importantly, is there a downside to this technology?

No Key Necessary

A keyless ignition allows you to fire up your car's engine without fumbling for a key in your pocket or purse.

How Keyless Ignition Works

Keyless ignition systems come with a fob that you can keep tucked away in your pocket, purse, briefcase, or anywhere in close proximity to the receiver inside the vehicle. The fob transmits a unique low-frequency signal to the car's computer system, which then validates that the correct signal has been sent and allows you to push a button on the dashboard or console to start the engine. Shutting off the motor is just as hassle-free: Simply press the start/stop button. And, in addition to keyless ignition, most systems also include keyless entry, allowing you to enter the car without inserting a key or hitting a button on the fob.

Even though keyless ignition has become widely available, even on affordable vehicles, these systems haven't yet reached the status of automotive necessity, as have power windows and door locks. Still, the convenience factor is a selling point for many car shoppers. It can be particularly helpful for drivers with arthritis or other disabilities that impede their ability to grip and turn a key.


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Security Measures

Keyless ignition systems contain safeguards to ensure that your car doesn't spring to life at the wrong time. Pre-start safety checks by the car's computer ensure that the vehicle is in park and that your foot is on the brake before allowing the engine to start. For added insurance, some designs require you to flick or rotate a switch before pressing the start button. And in most cases, the key fob must be inside the vehicle in order to get the motor running.

Among other advantages, these systems are designed to help deter break-ins and vehicle theft. Since the car's computer will only recognize a signal from its own fob, thieves will have a harder time getting in and starting the engine. There's no metal key that can be copied and no mechanical steering-column lock that can be forced or otherwise defeated.

Keyless ignition also makes it more difficult to lock your keys in the car or the trunk. For one thing, the fob can remain safe and snug in your pocket at all times. But some systems are smart enough not to allow the doors to lock if, for some reason, you leave the fob inside the vehicle or in the cargo area. Others send an audible alert if you attempt to shut a door or trunklid with the fob still inside.

And if the fob's battery goes dead while you're away from home, most systems have you covered, though the approach varies among carmakers. The most common solution is remote unlocking via the manufacturer's over-the-air emergency service. When you call or use the company's mobile app, a representative can send a signal to unlock your car doors and activate the starting system. Other automakers offer an emergency roadside assistance program that will send a technician to bail you out. And some systems even have a hidden key that pops out of the fob to unlock the door. The key can then be inserted into an emergency port to start the car.

The Problems With Keyless Ignition Systems

Unfortunately, there have been a number of unexpected, and sometimes tragic, dangers associated with keyless ignition. And although automakers and the National Highway Traffic Safety Administration (NHTSA) are taking measures to address these issues, you should be aware of the potential downsides to these systems.

With keyless ignition, and in light of today's exceptionally quiet engines, it's not difficult to forget to turn off the motor when leaving your car. Since 2006, more than two dozen people have died from carbon monoxide poisoning after leaving a car running in an enclosed garage that was attached to a house, and many others have suffered illness and injury.

Many people have also been injured or suffered property damage as a result of getting out of a vehicle without first putting the transmission in park. With a softly running engine and no key to disengage, drivers can inadvertently step out of the car while it's in gear, allowing it to lurch forward, dragging them along with it, and possibly running into another vehicle, wall or other obstacle.

You should also be aware that vehicles with keyless ignitions can be more vulnerable to hacking than those with conventional starting systems. Research teams have demonstrated that with the right equipment it's possible to "capture" the radio signal from a keyless fob and use that signal to open, and even start, the car. This kind of theft is a lot more complicated than smashing a window, but some determined and technically astute criminals have already broken into cars this way.

What's Being Done?

Automakers have responded to the problems associated with keyless ignitions by implementing a variety of solutions. Some models sound an alert, either by honking the horn or triggering an alarm, if the ignition fob is removed from the vehicle with the motor idling. Some vehicles are equipped with devices that automatically shift their transmissions into park when a door opens. And a few systems will automatically shut off the engine if it's left idling for more than a specified amount of time.

The NHTSA has proposed several regulations that would make some of these types of safety features mandatory for all keyless ignition systems, but to date, no federal rules have been instituted. In the meantime, automakers say they are in the process of voluntarily developing new ways to protect the public from the potential dangers of keyless entry and keyless start.

How to Protect Yourself

First and foremost, the NHTSA suggests reading your owner's manual carefully to be sure you know how to operate your vehicle's keyless ignition system properly. The agency also says it's essential to develop good driver habits, such as making sure your car is in park and the engine is shut off before departing from the vehicle. The NHTSA also suggests watching its video on basic safety tips for living with keyless ignitions.

It's also smart to research the systems while you're shopping for a new vehicle. Many of the latest models are now equipped with alarms and other safety devices that prevent drivers from leaving them running or in gear: If the cars you're considering have keyless ignition systems, make sure your next car has these kinds of safeguards, too.