What is cruise control and should you have it on your next car?
Cruise control can take the strain out of long drives and save you from a speeding fine – here's how it works, when to use it and what adaptive cruise control systems do...
Modern cruise control is an electronic system that controls the speed your car travels at. Once you’ve set it, the car will carry on driving at the speed selected without you needing to have your foot on the accelerator pedal.
It’s a useful aid for when you’re driving on motorways or A-roads that stops the car’s speed from creeping upwards unintentionally and ensures you don’t break any speed limits. It’s also good for easing foot fatigue and strain on long drives.
What is adaptive cruise control?
More complex adaptive cruise control (ACC) systems alter the speed the car is travelling at to keep it a set distance from the vehicle in front, and some systems can keep control of the driving in stop-start traffic jams.
The most advanced cruise control systems also work with a car’s advanced driver assistance features to ensure the car stays in its lane, in the right place on the road when cornering and reacts to avoid potential collisions with other vehicles and road users.
Some systems work with the car's speed-limit recognition technology and are able to automatically adjust the vehicle's speed accordingly.
How does cruise control work in a car?
Older cruise control systems controlled a vehicle's speed with a cable, but the latest versions use electronic sensors, speed detectors (such as radar) and a control module to ensure the car maintains a constant speed from the vehicle in front. They allow the driver to set their desired speed and stick to that even if the car goes up or down a steep incline.
Buttons to set and cancel the cruise control are often sited on the car’s steering wheel, but they can also be located on a stalk control, either as a dedicated unit or integrated into the indicator stalk. To activate the cruise control you should accelerate to the speed you want your car to travel at, and then press the set button. Many systems let the driver adjust the distance between their car and the one in front.
There are also buttons that allow you to increase or decrease the set speed by increments of 1mph without touching the accelerator or resetting the system. Often you can vary the speed in 5mph increments by pressing these buttons for longer.
Cruise control can be overridden by the driver by tapping the brake pedal, and you can still accelerate in the normal way. Some systems will continue to work afterwards if you’ve intervened briefly to make a manoeuvre such as avoiding a pothole.
Some cruise control systems also have short-cut controls to reactivate cruising at the previous speed with a single pull of a lever or tap of a button.
When should you use cruise control?
Cruise control is best suited to long-distance motorway or A-road driving when you’ll be driving for miles without any speed limit changes and with minimal steering input. Most systems only work at speeds above 25mph, so you’re unlikely to be able to use it on busy, urban roads where the average speed is low and you’ll be doing a lot of stop-start driving.
When shouldn’t you use cruise control?
Standard cruise control isn’t good for roads with lots of bends or stop-start traffic because you may have to deactivate the system frequently while negotiating these.
However, some of the most sophisticated adaptive cruise control systems are able to bring a car to a halt in its lane on a motorway if there is a brief traffic jam and then pull away again as the other vehicles start to move.
These systems use radar to monitor the speed of other vehicles and this means they can be better than the driver at anticipating hold-ups and slowing the car down in good time. Other systems use the car's own sat-nav to read the road ahead.
It’s not recommended to use cruise control in very bad weather, such as torrential rain, hail, fog or snow because these conditions can reduce the ability of the sensors to properly detect other traffic.
We also wouldn’t advise using cruise control if you’re feeling tired because, with less to do behind the wheel, there’s more danger that you could fall asleep.
Can you brake while using cruise control?
If your car has adaptive cruise control it will automatically apply the brakes and accelerator to keep the car a set distance from the vehicle in front.
However, if you need to brake manually to avoid an obstacle or other unexpected danger while the cruise control is on, you should do so. On most systems, this will deactivate the system, and you will have to reactivate it, although some will restart automatically after you’ve intervened. If you only want to decrease the speed by a small amount, the easiest way to do this is to use the minus button on the cruise control system.
How can I tell if my car has cruise control?
The best way to check if your car is fitted with cruise control, and if so what type and how to use it, is to check your owner’s manual. However, if the car has buttons on the steering wheel that say ‘cruise’, ‘cancel’, ‘res’ and ‘set’ these will be the cruise control switches.
Is cruise control expensive?
Many new cars come with cruise control as standard equipment, so if it’s a feature you’d like, check the spec of any potential purchase up front.
If you have an older car, or a model that doesn’t have it fitted, you can have it retro-fitted by a specialist at a cost of around £300 to £500.
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