Car Traction Control Explained
So What Is Traction Control Exactly? In short, traction control is a system installed into the design of a car...
So What Is Traction Control Exactly?
In short, traction control is a system installed into the design of a car to enable them to be able to form traction, or friction, on any road surface – in particular, road surfaces that are so smooth that there is minimal natural friction created between the car’s tyres and the road itself.
Low friction roads can be exacerbated by weather and environmental conditions like ice, rain, snow or gravel – all of which are likely to make tyres slip when driving upon them. If a car slips on the road, it makes it hard to impossible for a car to accelerate due to the lack of grip that is on the road. This is when traction control comes into play. The car activates the traction control system when it realises that the wheels are not gripping the surface. The system simply makes it easier for the wheels to grip the road by using any friction that is available. For this reason, cars with or without traction control will not be able to move off if there is absolutely no friction on a surface. This can be the case if the car is on ice.
So When Should I Use Traction Control?
Given that traction control is a system installed so that cars can accelerate and move off safely in all weather conditions that reduce the friction on roads, it is a good idea to activate the systems when road surfaces are covered in rain, ice or snow. Additionally, if the road surface is loose, bumpy or uneven, it is a good safety measure to activate the traction control of a car at this point too – even more so if you are on a road that is very much in need of some maintenance.
In terms of practical examples, cars that have traction control should think about activating in the following situations:
- Speeding up at green lights when roads are icy and the traffic is heavy and building up behind you
- Increasing speed when climbing a hill and the road surface has become loose and is covered in gravel in places.
- When moving through a small area of slush on a road that has forced the vehicles and the cars around it to slow down
But How Does Traction Control Work?
Those that are familiar with the anti lock braking systems that are often installed in cars will note many similarities between that system and traction control. In fact, some consider traction control to be supplemental to anti lock braking systems, or ABS for short.
Traction control and ABS have some of the same components. They are:
- Sensors that pick up and monitor the speed of wheels as well as the rotation speed. These can either be just on the front set of wheels or all four.
- The hydraulic modulator that works with the brakes
- The central electronic hub that is the control unit. It is this unit that receives the data from the sensors on the wheels and then tells the modulator to pump the brakes.
Both the ABS and the traction control systems work at the same time from the electronic hub, or the Electronic Central Unit or ECU. In addition, the hydraulic modulator works for both systems from this hub too. Some say that whilst they have different final functions, the ABS and traction control are so closely aligned they can sometimes be seen as the same system given they are both run from the ECU.
It is the ECU that is constantly monitoring your car’s wheels and whether your wheels are all spinning at the same speed or one is quicker or slower than the others. If the ECU does sense this, it can be a sign that one of your wheels has lost some much needed traction. At this point, the hub tells the hydraulic modulator to work the brakes in quick succession so that pressure is applied and released several times over in a very short space of time. The aim is to slow the speed of the wheel that is running too quickly. Another alternative to using the hydraulic modulator is simply to reduce the engine’s power or thrust that is sent to the wheel that is in danger of slipping. Only once the traction has been rebalanced on all wheels, the ECU and the engine then allow the wheels to run normally while continuing to monitor vehicle speed.
Drivers with cars with traction control need to be aware that when a car lowers the amount of power to the wheels so the rotation slows down to stop slipping, there may be the feeling of the acceleration or gas pedal vibrating. It’s good to know that this is a characteristic of the traction control as it can be disconcerting the first time it is felt. The car is behaving normally and there is nothing wrong with your vehicle should this occur.
That’s All Very Well, But Does Traction Control Actually Work?
The answer to this question is not particularly straightforward. In the main, traction control is actually fairly effective, especially when you want your car to move off or speed up in situations where the road has little to no friction. However, it has been seen that traction control is far more effective in cars with four wheel drive as opposed to just front wheel drive cars. Furthermore, traction control has even more effectiveness when engine power is reduced to the wheels to slow down rotation. This was found to improve the overall stability of the cars that used this method, however it was also found that cars that purely used a braking system were good to use when trying to increase the performance of the acceleration of the car.
Ultimately, the success of traction control is not so great that it has been seen to reduce the amount of crashes on the road. However, many cars incorporate it as standard with the auto braking system as a matter of course as well as sometimes being packaged up with electronic stability control. Therefore it is unclear as to what of these three improves the safety measures of a car, but when they are all used in conjunction with one another, a car is more secure to drive.
What are the Limitations of Traction Control and its Uses?
Unfortunately, the answer to this is far more easy to come to. Sadly, there are definite limitations to traction control. In the main, however, these come from the inappropriate use of it by drivers themselves, not the actual system. For traction control to be useful, it has to be used properly in the conditions that demand it. Therefore, if drivers still continue to speed or to practice tailgating, there is a limited amount that traction control can do to keep drivers and passengers safe.
Drivers also need to be aware of their speed in comparison to the road they are driving on and the conditions that the road is in. Traction control is not installed in cars to reduce stopping distances so if drivers are out in icy conditions, they need to remember to drive a much further distance from the car in front of them. In addition to this, as traction control means that cars are likely to run at higher speeds in slippery conditions, because the system is allowing for greater grip on the road, driving can feasibly become more dangerous at times given that stopping distances do not decrease. This is obviously an unsafe side result of having traction control in a car. It is fine if drivers continually monitor their speed and change it according to what the conditions demand, but this is not always the case.
In this way, it is sometimes argued by safety experts that traction control can actually cause people to be less risk averse on the road which can be dangerous especially as traction control does not help those on the road to stop any quicker.
That being said, traction control does have its obvious benefits especially if it is used by drivers who practice safe driving otherwise. This includes using caution when necessary and not partaking in any journeys that are to be carried out in unsafe conditions like snow.
Is Traction Control Used Very Much Therefore?
Traction is far more common than we think these days and it often comes as standard in many cars, particularly ones that have ABS too as the two are so often so closely linked. The technology has been around for a while, even as far back as the the 1970s so it is fairly well used across the car industry.
Bearing this in mind, it obviously is far more beneficial to have than not at all. So as long as good driving technique is used alongside any traction control system, it is a good one to have within any car.