What is keyless entry?

Doors that open with the brush of a hand, bootlids that lift with a wave of your foot: welcome to keyless entry

BuyaCar team
Dec 8, 2021

Ever find yourself scrambling through bags, drawers and pockets to find your car keys? A car with keyless entry might be exactly what you need.

Keyless entry is a clever system that allows you to unlock car doors without handling the key. The car automatically senses when the fob is nearby and unlocks the doors for you, meaning the key can be stored in a pocket or bag and simply left there. Your car will also lock its doors once you have turned off the engine, left the vehicle, closed the doors and walked away. As long as the key is on your person, the car will take care of locking or unlocking the doors on your behalf.

Keyless entry is becoming more popular on cars of all shapes, sizes and prices, so if you’re looking for a more convenient way to lock and unlock your car, keyless entry might be perfect for you.

How does keyless entry work?

Keyless entry systems work using radio signals that are emitted from the car and a key fob that searches for those signals. When you place your hand on the door handle of a keyless car (in some cases you have to press a button), the vehicle will send out a short-range radio signal. If the fob is within range of the car's radio waves, usually around 5 metres, it will send its own signal back to the car and the vehicle's onboard computer will unlock the doors.

The same process takes place when you need to start the engine, but with a button located on the inside of the car that brings the engine to life. Usually, the car’s onboard computer can determine whether the fob is located inside or outside of the vehicle, and will only allow the engine to ignite if the key is inside the cabin.

Keyless boot opening systems are also becoming increasingly popular. Simply waggle your foot underneath the car’s rear bumper and the boot will open automatically. A useful feature for visits to the supermarket where your hands are often laden with heavy shopping bags.

There are even some cars that store a version of your key on your phone, so you can unlock the car without even having a physical key on you. Some BMWs, Teslas and the Ford Mustang Mach-E offer this capability.

What are the problems with keyless entry?

Your car doesn't automatically switch off the engine and lock itself if the fob goes out of range. This is to ensure that you're not suddenly stranded in the middle of the motorway if its battery dies. Keyless cars may also go through key fob batteries quickly, too.

However, this also means that you could drop someone off who has the key fob in their bag or pocket and then drive away. As soon as you turn the engine off, you won't be able to start the car again. Also, in most cases you will still need to have a physical key fob and somewhere to put it, so you’ll still need to remember where you placed the key before you can hop in the car and drive away.

There are also serious concerns about the security of keyless entry systems, with a number of ways that thieves are able to breach them. In 2011, researchers from Zurich showed how the radio signals emitted by cars could be boosted, tricking it into thinking the key fob was nearby. Police have investigated criminals who block the signals from keyless devices, so that car doors never lock, and there are also allegations that thieves can intercept the codes that are transmitted between key fob and car.

In 2014, after a spate of Range Rover thefts, police advised owners to fit a steering wheel lock as a second line of defence against thieves who were able to overcome keyless security. Land Rover subsequently issued a fix for their cars.

Security experts recommend that you keep keyless entry keys away from doors and windows to stop thieves from stealing the signal and replicating your key from outside your house. A shielded protection case can provide additional protection by limiting the distance frequencies emitted by the key fob can travel. The most popular protective cases are called Faraday pouches and can be picked up from auto parts stores for under £10.

Some manufacturers are now including technology that should prevent keyless car theft, such as a ‘sleep’ mode that prevents the key’s signal from being transmitted if it’s not used for a few minutes. But it’s still worth taking your own precautions if you have a car with keyless entry, even if it’s just for your own peace of mind.

 

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