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Traction Control

Basic Description

A traction control system prevents wheel spin from occurring due to a loss of traction during acceleration. This usually happens on a slippery surface, such as snow or wet road, where the wheels are not able to generate enough traction to move the vehicle. Antilock braking systems (ABS) also prevent a vehicle's wheels from slipping due to a loss of traction. The major difference between an ABS and traction control systems is that ABS stops the wheel from losing traction while braking, while traction control stops the wheel from spinning when the vehicle is accelerating. Traction control systems are often referred to by other names (e.g. anti-slip regulation or stability control); however traction control is not the same as electronic stability control or active yaw control.

Traction control systems use wheel speed sensors to determine the rate at which the drive wheels are rotating. They detect if there is any slip occurring between the tire and the road. If slip is detected, the system slows the wheel by applying the brake or reducing the torque to that wheel until it is able to generate the required amount of friction for the vehicle to move. In vehicles with a standard differential, applying the brake to a slipping wheel, increases the amount of torque delivered to the opposite wheel, which may have better traction. If both the driven wheels are losing traction, traction control systems usually slow both the slipping wheels equally until they regain traction.

With and Without Traction

Some performance vehicles provide the option to switch off the traction control system.

Wheel speed
Brake control module, warning light
Data Communications
High speed CAN
Bazzaz, BMW, Bosch, Continental, Racelogic
For More Information
[1] Traction Control System,Wikipedia.
[2] Traction Control Explained, How Stuff Works, Sep. 7, 2005.
[3] Active Traction Control, YouTube, Jan. 29, 2010.
[4] Toyota Traction Control System, YouTube July 17, 2011.
[5] Mitsubishi's Active Stability Control, YouTube, Dec. 11, 2013.
[6] High Efficiency Traction Control (HET) by Bosch Rexroth, YouTube, Feb. 3, 2014.