How to make cruise control yourself?

Cruise control - what is it? A system required for long trips when the driver is extremely attentive. Cruise control is in demand in countries where there are long straight roads.

Most drivers who bought a used foreign car (even a very expensive one) often have no idea about the functionality of their car. Many drivers ask the question: “Cruise control - what is it?”

The key-based device, which is built into the steering wheel of a car, is not used after activation does not lead to the desired result. This article will tell you how to install cruise control yourself and what it is.

Modern cruise control systems are either passive or adaptive.

Cruise control - what is it?

Few people have not heard such an expression as cruise control. The functions of this device are known - automatic adjustment of vehicle speed, which reduces the load on the driver. From the article you will learn the history of the appearance and development of this device, the principle of operation, its strengths and weaknesses, features of installation and use on various cars.

History of appearance

The invention of the cruise control system is credited to blind inventor Ralph Titor, who received a patent for the device in 1945. In 1956, this device was installed as an experiment on the newly developed GAZ-21 Volga, however, such a car did not go into production. The device monitored the speed of rotation of the crankshaft and, if necessary, adjusted the fuel supply. In 1958, Chrysler began commercially installing cruise control on some models. By 1965, American Motors (AMC) began producing inexpensive cruise control models that were widely installed on trucks and tractors with automatic transmissions.

How is cruise control different from adaptive cruise control?

What is cruise control? Unfortunately, many car owners know about this function only superficially. What is adaptive cruise control? We think, friends, that not many drivers will be able to answer this question in detail and in detail, despite the fact that this technology has long appeared in the automotive industry. Let's find out together today in more detail what this useful and, at the same time, very amazing function (option) in modern cars is.

So, dear drivers, what is cruise control? Cruise control is an electronic system that automatically regulates vehicle speed without driver intervention. That is, the cruise control system allows the driver to take his foot off the gas pedal while driving the car. This is the simplest explanation that, in principle, fits the basic description of the classic cruise control system. But these days, many automakers are adding more and more advanced cruise control systems to their cars every year, which make the process of driving much easier and safer.

Also, many modern cruise control systems have now become an intermediate stage in the transition of the entire automotive industry to the full autonomy of a modern car, which in the future, according to experts, will be able to completely operate without a driver.

See also: The most popular options in cars in 2021

When this cruise control was the preserve of only high-luxury cars. Some 20 years ago it was impossible to know what cruise control was; only the owner of an expensive luxury car could find out. Today, when the cost of this technology has dropped significantly and significantly, automakers have begun to equip even economy-class cars with cruise control.

Today we can get such cruise control for ourselves even in the cheapest and least prestigious small cars. Just 10 years ago this seemed like a fantasy to many.

How does cruise control work?

This device monitors the vehicle's speed and adjusts the fuel supply based on it. To estimate speed, signals from ABS sensors are most often used, this avoids unnecessary complication of the system. When the CC is turned on, its control unit remembers the number of ABS sensor pulses per unit of time. If the number of pulses has increased, it reduces the fuel supply; if it has decreased, it increases it. If the cruise control is coordinated with the automatic transmission, then the gears are switched depending on the load. On a manual transmission, this work has to be done by the driver. In most cases, the fuel supply is controlled using a servo or motor with a gearbox, which regulates the position of the throttle valve.

Advantages and disadvantages of the system

The advantages of this device are obvious - reducing the load on the driver. This is especially important during long trips along the highway, lasting more than one hour. The driver's leg does not get tired, because the control unit automatically increases or decreases the fuel supply, so the speed does not change. However, this device is not without its drawbacks. Any malfunction in its operation can lead to an accident, because it independently regulates the fuel supply to the engine. Another drawback is that this device relaxes the driver, which causes his concentration to decrease. This can also lead to an accident.

Is it possible to do a cruise on your own?

When making a CC yourself, the following questions arise:

where to get a diagram that does not need to be altered to fit your car;

where to get a servo drive with suitable characteristics;

how to ensure overall system reliability;
how to avoid mistakes that can lead to tragedy.

A large number of different diagrams taken from production cars of the end of the last century are posted on the Internet. Finding parts for them is problematic because they are no longer produced. If you use modern circuits with microcontrollers, then no one knows how such a circuit will behave during some kind of failure. Perhaps it will lower the engine speed to idle, or maybe it will sharply increase it to maximum. If this happens at a sharp turn, tragedy cannot be avoided. Another problem is the servo drive, the pitch of which is tenths of a millimeter. This will allow you to smoothly regulate the speed of the car and avoid jerking.

Many DIYers suggest using a motor and gearbox from windshield wipers for this, however, this option is not very good due to high inertia and difficulties with adjustment. If you use the electronic gas pedal drive from a damaged foreign car, then why not take the control unit from there? Installing such a drive on a car with a throttle cable will require installing and connecting a servo drive to the throttle valve. All this allows us to conclude that you can do cruise control yourself if you are well versed in electronics, have access to the component base and can carry out a serious modification of the car yourself.

How much does a cruise system and its installation cost?

The cost of inexpensive cruise control models that provide a minimum number of functions (maintaining and smoothly adjusting speed) starts from 10 thousand rubles. The delivery set includes a control unit and a servo drive. More expensive models, the cost of which reaches 30 thousand rubles, are equipped with an LCD display that displays the operating mode of the CC and the main parameters of the car, and is also capable of self-learning. Often such units are equipped not with a vacuum, but with a completely electric servo drive, which does not require intervention in the operation of the vacuum brake booster, so its installation is several times simpler.

When choosing a cruise control model, keep in mind that all electronic components officially imported into the Russian Federation or produced domestically must have the following documents:

passport in Russian, which describes in detail the characteristics, device and installation;
certificate of conformity issued by the Federal Agency for Metrology and Technical Regulation.

If you purchased the installation kit for a vehicle other than yours, you will have to buy the wiring separately or make it yourself with the appropriate connectors. The cost of installation is 2-5 thousand rubles and takes 1-2 hours. The installation also includes a full setup of the cruise control and testing of its operation. If the CC is installed on a car with a mechanically driven injector, fuel injection pump or carburetor, you need to buy an electronic gas pedal sensor. This will allow you to turn off cruise control by pressing the brake or gas pedals, which increases the safety of driving.

Tools and materials

Before installing the CC, be sure to check all components and safety systems of your machine for malfunctions. Otherwise, do not be surprised that the cruise does not turn on, or the car behaves inappropriately when trying to maintain the set speed.

The set of tools to perform such a task will consist of:

How to install cruise control on a car yourself

To install the CC yourself you will need:

cruise control installation kit;
electrical diagram of your car;
wiring for CC corresponding to your car or suitable connectors and mounting wire;
electronic gas pedal sensor (only for vehicles with manual throttle control);
a tee and a hose, the diameter of which is equal to the diameter of the hose of the vacuum brake booster (only for CC with a vacuum servo drive);
a fuse whose current is 50 percent greater than that indicated in the passport of the KK control unit;
tester;
drill;
a set of keys;
a set of screwdrivers of different lengths and thicknesses;
various nuts and bolts for attaching the servo drive and control unit;
insulating tape;
Ability to read schematics, connect wires, and perform complex plumbing work.

Using the diagram, locate the wire that transmits the ABS sensor signals. If your car does not have one, then the wire that transmits signals from the electronic speedometer. If it is not there, then the wire is the tachometer, crankshaft position sensor, camshaft or electronic ignition control. From this wire, the CC controller will receive data on the vehicle speed or engine operation, from which it will determine whether it is necessary to add or reduce the fuel supply.

After this, locate the wire connected to the brake sensor that turns on the brake lights. From this wire the CC controller will receive a signal that turns off its operation. Next, locate the wire from the electronic gas pedal sensor. If you have a mechanical pedal, connect a sensor to it. Locate the wire that supplies the ignition ON signal to the injector controller, electronic ignition, or diesel fuel valve. The KK control unit must be connected to this wire. To connect the servo, find the wire for the generator or power supply to the ignition coils.

Find a location on the front panel to install the buttons and QC indicator. In the engine compartment, find a place to install the servo drive. The distance from it to the throttle valve should not exceed 2/3 of the length of its cable. Find a place to install the control unit. It is advisable to install it in the cabin under the front panel.

Disconnect the battery.
Secure the servo drive and control unit. If you have standard wiring, then lay it so that the wires do not dangle and connect it to the appropriate connector and connect the fuse. If there is no standard wiring, assemble it based on the car diagram and pinout of the control unit contacts, and also connect the connector to the standard wiring. Install the fuse.
Connect the wiring to the CC control unit and the servo drive.
After this, be sure to check that you have connected everything correctly.
If everything is fine, start the engine, accelerate the car and check the operation of the cruise control.

Cruise control classification

Such devices are usually classified as follows:

Passive - inexpensive and simple devices. Such CCs can only maintain a constant level of machine speed.
Adaptive is a more modern type of cruise control. Such systems can set a variable type of vehicle speed, as well as maintain a distance between cars. Adaptive cruise control is used on cars equipped with ESP and ABS, as these systems work together.

The process of installing cruise control is a complex operation that should be carried out by professionals. If the technician is not sufficiently qualified, more serious problems affecting ESP and ABS may occur.

Types of cruise controls

There are two main types of cruise control - passive (PCC) and adaptive (ACC). The first type is a classic system that has been used on cars with manual and automatic transmissions for over 40 years. It is activated via buttons or levers on the steering wheel and simply maintains a constant speed.

Passive Cruise Control is deactivated when the driver presses the brake pedal. However, these settings can be changed. You will find detailed information in the manual.

Adaptive cruise control

However, adaptive cruise control . What it is? This is a complex that not only maintains a constant speed, but also regulates it depending on the obstacles that arise on the road (vehicle ahead, obstacles, and so on). To do this, it constantly measures the distance to the vehicle ahead (usually at a distance of up to 200 meters).

Based on the principle of operation, adaptive cruise controls are divided into two types - laser and radar . As the name implies, the former use a laser beam for their work, the latter use radio waves. Laser systems are much cheaper, but have significant drawbacks, which is why they are not widely used. In particular. the laser does not work well in cloudy and foggy weather, and it is also difficult to distinguish between dirty cars. Radar systems, in turn, do not have these disadvantages, which is why they are installed on expensive cars (business and luxury class).

ACC indicator

The ACC radar sensor is installed behind the radiator grille and constantly sends signals, recording the distance to the nearest car in front. If it slows down or a third object appears between your car and another car, the sensor sends a signal to the Cruise Control System to reduce speed. In this case, not only the engine is used, but also the car's braking system . If the road is cleared again, speed will be restored. On Toyota and Lexus, a similar sensor is used by the pre-crash safety system. You can read about this in another article.

PCS system error

The pre-collision safety system (PCS) is responsible for avoiding a collision and in the event of a failure of the sensors or control unit, it displays the check pcs error on the instrument panel in order to warn the driver Read more

The distance at which the system operates is 200 meters, and the speed range is 40...210 km/h (these values may vary slightly for different cars). The device can completely stop a car in a traffic jam and start moving within the first three seconds when the road ahead is clear.

Available Brake Assist alerts the driver to danger even when adaptive cruise control is turned off.

ACC work

In addition, ACC has a number of additional functions. For example, it can be used to change the speed of a car. This is done by gradually increasing or decreasing the speed by 1...2 km/h (depending on the car model). In this case, the complex does not care how loaded the car is or how steep the slope you are climbing. Also, adaptive control, in the event of danger or the likelihood of an emergency, notifies the driver using visual or audio signals (sometimes both).

Car brand name	ACC name
Toyota	Radar Cruise Control
Mitsubishi	Preview Distance Control
Mercedes-Benz	Distronic (Distronic Plus)
BMW	Active Cruise Control
VAG (Volkswagen, Audi)	Adaptive Cruise Control
Honda	Adaptive Cruise Control

Adaptive Cruise Control always works in conjunction with the vehicle's two safety systems - ABS (anti-lock braking) and ESP (electronic stability control), if equipped. If at least one of them does not work, ACC will not turn on.

Remember that cruise control is not intended for driving in difficult conditions (including in the city). It only needs to be turned on on country roads where there are few cars, or all of them are driving at approximately the same speed. This also applies to adaptive cruise control.

Features of installing cruise control

Before you begin installing the device, you should pay attention to some features:

You can't install cruise control on just any engine, so you need to make sure that the car's engine is compatible with the device.
The simplest is to install the passive version of the CC, which does not require additional devices. For the adaptive system, the correct operation of ESP and ABS is important, since without them the cruise control will not be able to function.
During installation, there is no need to reflash the ECU, since only the device itself will be mounted.

↑ That's probably all.

After the article I will write detailed instructions for manufacturing and installation. For what? Yes, I’m used to doing everything carefully and bringing it to the very end. What's next? I'm looking forward to building a tube amplifier, my hands are itching right from my ankles! I really hope for help, as with cruise control, from the residents of Datagoria. Thanks to: Igor (Datagor) for the site and the opportunity to receive and provide assistance, Volodya (hippo65), Zhenya (nightmare), Misha (mikky) for help in writing the program and making the device, Sasha (alexander59) for support, Slava (SlavaSAS) from the Microb website for the lever, faith in me, support, as well as to everyone who took part in the discussion of the device and helped with criticism and advice.

Cruise control installation instructions

The installation of cruise control on cars with an automatic transmission (automatic transmission) or manual transmission (manual transmission) differs slightly. The action plan is as follows:

Replacing the brake sensor. To do this, you need to disconnect the wiring and carefully pull out the sensor with several turns. The new device is installed by holding the pedal assembly in the raised position. The sensor itself is part of the cruise control and is included in the package.
Installing a cruise control button for easy control of the system. You will have to dismantle the airbag, unscrew the back of the steering wheel, remove the plug, and then proceed to install the button itself.
Conducting testing. After all the work has been completed, it is necessary to test drive the system, maintaining maximum safety. If there are no complaints about the operation of the cruise control, we can assume that the work was successful.

Device

The ACC system contains its own components and devices, and also uses those already available on the car:

obstacle detection radars or lidars with different ranges, while radio frequency sensors work better in conditions of difficult visibility, precipitation or fog;
accelerator pedal or electronic throttle activator;
microcomputer system control module;
sound and light indicators, information board and push-button control panel;
communication interfaces with ABS and ESP systems;
brake and accelerator pedal sensors.

The basis of the device is a control program containing all the complex algorithms for ACC operation in a wide variety of conditions.

Purpose and benefits of cruise control

The main advantages of cruise control:

long trips tire the driver less, since there is no need to fix the legs in one position and monitor the speed;
constant speed reduces fuel consumption;
traffic safety increases.

The cruise control system requires proper maintenance, without which problems may occur while driving, such as the car braking for no reason, etc.

It makes no sense to install a cruise control system when using a car on city roads, since in this case it is not possible to maintain a constant speed. But cruise control is ideal for drivers who often travel long distances on intercity highways. In this case, the benefits of the device significantly outweigh the costs of installation and maintenance.