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Cruise control: how it works, how to use

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Cruise control: how it works, how to use
Cruise control: how it works, how to use

Cruise control, or “autodrive”, in a car is a software and hardware system that is designed to maintain speed in a certain area. At the same time, the participation of the driver is not required - you can relax on a long journey. Feet can be removed from the pedals and kept on the floor. This system first appeared in 1958. She completed the Chrysler Imperial. This system is in many modern cars, it is also found in old foreign cars. And for installation on domestic cars, there are special kits.

Operation principle

Cruise control can work in different ways, but the following system is most commonly used. In the simplest case, this is a negative feedback servo connected by a cable or rod to the throttle mechanism. If the speed of the car is constant, then the accelerator is pressed to some specific, constant angle of inclination. If you turn on the system, the control unit will remember the position of the pedal and fix the speed.

cruise button

If the speed decreases while the car is moving, for example, on the rise, the control unit will give a signal so that the throttle angledamper has changed. The accelerator pedal angle depends on the error signals. It will be so until the speed goes up.

When the speed increases, the ECU will send a corresponding signal to the servo, and the fuel supply will decrease. In this case, the fuel supply may decrease up to idling. But here various options are possible, and it all depends on which cruise control is installed in the car.

If the gearbox is mechanical, then the accelerator sector can rest against a special stop, limiting its further movement. In this case, the control unit will prompt the driver to change gear. If the car is equipped with an automatic transmission, the gear will change automatically. When the speed reaches the level set by the driver, the servo will stop and the accelerator sector will return to its position.

Types of systems

There are now two kinds of cruise control systems. These are adaptive and passive options. The first type is a classic system used on both manual and automatic vehicles for more than 40 years. Starting is carried out using buttons or levers. Such a solution can only maintain some kind of constant speed. Passive speed control will disengage if the driver presses the brake or accelerator pedal.

Features of adaptive systems

Adaptive cruise control is much more interesting technically. This is a software and hardware complex, which, unlike a passive analogue, can not only maintain a constant speed set by the driver, but also regulate the speed depending onroad conditions.

cruise control

For this, there are various sensors that measure the distance to cars moving in front.

How the adaptive system works

The operating principle can be divided into two types. Laser and radar modifications can be distinguished. In the case of the former, a laser beam is used to measure the distance to the car in front. In the second case, a radio wave is used to solve the same problem.

Systems built on a laser beam have a lower cost. However, for this reason, they also have a lot of limitations and shortcomings, due to which they have not become popular. So, the effectiveness of the laser beam is significantly reduced if it is cloudy or foggy outside. Also, the laser may be mistaken if the car in front is dirty.

Radar systems do not have all these shortcomings, but they can only be found on premium cars. The sensor is installed behind the grille. As it works, it constantly sends a signal and then records the distance to the vehicle in front. If this car slows down or the distance to the car is reduced, if another object appears between the cars, the system will send a signal to reduce the speed. In this case, not only the power unit will be involved for braking, but also the braking system. When the road conditions improve and there are no obstacles, the speed will be automatically restored.

how to enable cruise control

Adaptive system works up to 200 meters away. Whereinthe speed it can maintain is in the range of 40 to 120 km/h. Speed ​​ranges may vary depending on the make and model of the car. The system can even bring the car to a complete stop in a traffic jam, and then start moving when the car ahead has pulled away.

How to use the system

Not all modern car owners know that such a system is installed in the car, so we will tell you how to turn on cruise control and how to use it. Often there are buttons on the steering wheel to control the complex. Manufacturers often place controls on multi-wheels. In rare cases, the controls can be seen on the steering column switches - this can be seen in old foreign cars.

cruise control ford

Getting started with this driver assistant is easy. There is a cruise control button for this. However, all cars are different, which means that nuances are possible.

In most cases, it is necessary to pick up the speed at which further movement is planned. It should be borne in mind that for the bulk of the systems, the minimum speed is 40 km / h. Next, the system is activated using the button - on it you can see the symbol of the tachometer. After that, the corresponding symbol will be displayed on the dashboard. The system is then activated using a lever or button labeled “Set”. Only then will the machine be controlled automatically.

set cruise control

If you need to decrease or increase the speed, there are buttons “-“and “+”. In this case, the speed will change step by step -it depends on the car. Some modern models have more flexible options for customization.

How to disable

The assistant is disabled depending on its type. For the simplest system, just press the gas or brake pedal. The control unit will then switch to normal driver-controlled mode. If this is an adaptive cruise, then you can turn it off by pressing the gas pedal. In other cases, the corresponding button is used.

The system will turn off automatically if the vehicle accelerates rapidly. Also, automatic shutdown will occur if the automatic transmission is in neutral gear.

How to install

Installing cruise control will make the car more comfortable. On sale you can find mechanical solutions, including those for carbureted cars, as well as blocks for an electronic gas pedal.

To install, you need to disconnect the negative battery terminal, dismantle the plastic parts of the steering wheel trim. Next, disconnect the horn connectors and remove the airbag completely. Then they mark and cut places on the plastic for future buttons. It is recommended to check everything carefully before cutting. After that, the controls are inserted into the prepared places, the wire blocks are connected.

cruise control installation

Cruise control, say, installed on a Ford Focus, after that you need to configure it using the appropriate software. On cars from AvtoVAZ, the installation scheme will be different. Here, in addition to the buttons, they also install a separate electronicblock.


As you can see, this is a useful system, but not always and not for everyone. It is convenient to turn it on on long trips. At the same time, the quality of the roadway must be very high. On roads with large pits and potholes, this solution is ineffective. But it's worth installing cruise control if only to make the car more technological.

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