You've seen this light illuminate on your dashboard before in a few instances. There's even a button to turn it off temporarily but what is Traction Control exactly?
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Simply put, Traction Control helps prevent loss of traction of the car's driven wheels to help maintain vehicle control. Loss of traction occurs with wheelspin. Wheelspin basically is when the torque applied to a driven wheel causes the tyre to break traction. An easy way to visualise this is the driven wheels rotate rapidly compared with the non-driven wheels. Traction Control is a safety system fitted to a large majority of modern cars. In recent years, it has become fairly ubiquitous, from premium cars to budget cars, from hair-raising powerful cars to humble runabouts. This system applies to front-wheel drive, rear-wheel drive and four-wheel drive cars. The system has been around since the 1970s and was typically found in high-power output, rear-wheel drive cars. Nowadays, they're a mandatory requirement in road cars.
How does it all work?
Traction Control is one of those passive-style safety systems that runs in the background and kicks in when an error state occurs. You can turn off Traction Control for some road conditions, though, which we'll get into in a bit. The system uses sensors on each wheel; typically, they can be the same ones the ABS system uses to see how much the wheels spin relative to each other and relative to the speed of the car. That information is sent to the ECU and when the sensors detect wheelspin at any of the wheels, the system kicks in. When the system engages, it intervenes by slowing down the spinning by either limiting power to that wheel or applying a small amount of braking force to that wheel. Early systems were quite noticeable in application, like a sensation similar to ABS or your vehicle hesitating until traction is regained. Modern-day Traction Control systems, however, are very subtle in such a way that you don't exactly notice the system engaging bar an illuminating warning light on your car's instrument cluster.
Note, that if your tyres are worn and or expired, compromising the level of grip available, you can see your traction control activating more often. It's good to keep on top of your tyre condition.
When is it a good idea to turn Traction Control off?
An instance when you would want to turn off Traction Control would be when you're in an off-road situation and get stuck in snow or mud. If you allow one wheel to spin faster, you can propel the vehicle forward with enough momentum to get it unstuck. Apart from that situation, it's wise to leave the system on for general road usage, particularly in slippery driving conditions such as rain. This prevents the vehicle from potentially skidding and causing an accident.
How do you turn off Traction Control?
Most Traction Control systems can be deactivated temporarily by a simple button press. The system reactivates when you turn off and turn on your car. When you are about to start your car and leave the vehicle in the 'Ignition On' state, you'll notice the Traction Control symbol illuminating, that's how you'll know the system is active. The light will turn off when the vehicle is turned on and running. If the symbol stays illuminated, even after the vehicle is turned on, there may be a fault with the system, and you'll need to have it diagnosed. The Traction Control button usually has the same symbol found in the instrument cluster or is labelled 'TCS', but different manufacturers have different interpretations. Deactivating requires you to press and hold the button for a few seconds until you see a light on your instrument cluster indicating that the system is off. In some cars, you can only deactivate Traction Control via the infotainment system.
