The purpose of traction control is to make effective use of any available traction from the surface that your vehicle wheels are in contact with when accelerating.
It does this by using sensors to detect wheel-slip, or wheel-spin of the drive wheels and if detected, the brakes are automatically applied and on some versions of traction control, power to the affected wheels is also reduced until wheel rotation is similar to that of the non-drive wheels.
On a low-friction surface such as a wet or muddy road, traction control will almost always benefit the driver. Traction control doesn’t create traction, but makes use of any traction that’s available – which is where traction control may not always help.
Traction control does work on ice up to a point. The ice that forms on roads varies from ice that’s textured and rough (low traction) through to a thin coating of glaze ice that covers the surface. This thin coating is often referred to as black ice and is almost frictionless, meaning zero traction is available.
On a frictionless surface, a vehicle with traction control will perform equally as poorly as a vehicle without traction control
Should you turn traction control off on ice?
As a general rule, always keep traction control turned on until such a point that it hinders progress. You may find for example that ascending a slope that is covered in ice very difficult with traction control switched on. With almost no traction on offer, the traction control system will consistently apply the brakes and cut power to the drive wheels, yet wheel-slip still occurs.
In this instance, turning off traction control and allowing the wheels to spin may gain greater traction. The wheel-spin will generate friction and heat which will ‘dig down’ into the ice. Not ideal, but if you have no other option, this might just be enough to get momentum.
If you are having trouble driving up an icy slope, then the safest option is to find an alternative route. If that isn’t an option, then try these tips:
- Before you start ascending the slope, gain speed and momentum, ensuring your speed is reduced as you reach the top of the slope so to maintain control. You can try this with traction control on and then off. If ascending the icy slope with traction control off, limit the amount of wheel-slip using clutch control and/or the accelerator if driving an automatic. If the vehicle begins to slid too much, dip the clutch or come off the gas pedal to cut engine power. Avoid using the brake.
- If you really can’t get up that icy slope and if you’re driving a front-wheel drive car, attempt going up the slope in reverse. More weight is distributed to the rear of the vehicle when driving up a slope. If driving up the slope in reverse and in a front-wheel drive car, it means more weight on the drive wheels which means more traction. Only try this is you have good visibility and are confident in your ability to control the vehicle.