Under the Hood: What is Traction Control?

What is traction control? Well, before we get into that, let’s talk about traction itself.

Traction is important; it’s the difference between moving forward and sitting still. Without any friction between your vehicle’s tires and the road surface you’d never make it to work in the morning, let alone to that Grand Funk Railroad concert on Saturday night.

Obviously, different weather conditions play a roll in driving; rain, snow and ice all reduce the amount of friction between tires and roads. Thankfully there are ways to outflank Mother Nature on the battleground of the highway. At least one technology is designed to help drivers grip instead of slip.

“Overall, traction control is meant to maximize your forward or reverse tractive capabilities,” said Chris Harrison, Manager of Vehicle Development and Test for Electronic Brake Systems at Continental North America.

Conti is a massive supplier company that sells parts and technology to automakers around the world. It’s probably best known for their tires, but it has a diverse portfolio of products ranging from chassis and safety systems to engine sensors and turbochargers.

But how does traction control work? What’s the mechanism behind it? Well, there are several ways it can function. One is through engine management. When slippage is detected, a vehicle’s control computer can cut the power flowing to the wheels, reducing spin and hopefully improving traction.

Another way these systems can operate is through braking. Harrison said “brake traction control works a lot like a locking differential, except we use the brakes to do that.”

By tapping into the ABS (anti-lock brake) system traction control can apply the brakes to just the wheel that’s slipping. A standard, open differential will then route power to the opposite wheel, which hopefully has more grip.

Either way the goals are the same, find traction and “try to be as transparent to the customer as possible” Harrison said. Nobody wants their vehicle to jerk or bang as the system engages. Smoothness and refinement are mandatory.

All of this is fine and dandy with front- or rear-drive, but all-wheel drive is just as important. Harrison said “in a four-wheel-drive application we’re able to transfer torque to the front of the vehicle or the rear of the vehicle,” understandably that’s a huge advantage when it comes to traction. To manage wheel spin these systems can use engine management, the vehicle’s braking system or a special part known as a center differential, if equipped.

SEE ALSO: What’s the Best All-Wheel-Drive System for You?

If caught in a slippery situation some people actually disable the system on their vehicle to allow wheel spin in hopes of getting some grip. But this is not necessarily beneficial.

“A lot of traction-control systems recognize if a vehicle is stuck,” said Harrison. They will actually allow for some wheel slippage to help find traction. A good example of this is spinning the tires to dig through snow in order to reach pavement. Still, his advice is “trust the system.”

“I can promise you a lot of people worked a lot of hours to optimize the system to make it as good as it could possibly be in winter conditions,” Harrison said.

There are instances where you’d want to turn off traction control, but they are extremely limited and come with risks.

Arguably, the only time you’d want to turn off your car’s traction control system is when it is stuck in mud, snow or on ice. Often, the way these systems work (by shutting down power when slippage is detected) can limit your ability to get out of a low-grip situation. Turning off the system can allow for just enough slip for you to be able to carefully get out of a slippery situation. We advise that once you do remove the vehicle from said situation, you should reengage the traction control button.

All vehicles will naturally re-engage the system by turning the car off and then on again.

Traction control can also be turned off when driving on a race track, but this comes with even more risk, as speeds and performance driving add in risk factors of their own.