Ministry of Transportation / Ministère des Transports
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I. Driving at night and in bad weather
Anti-lock braking systems (ABS)

If your vehicle is equipped with anti-lock brakes, practise emergency braking to understand how your vehicle will react. It is a good idea to practise doing this under controlled conditions with a qualified driving instructor.

ABS is designed to sense the speed of the wheels on a vehicle during braking. An abnormal drop in wheel speed, which indicates potential wheel lock, causes the brake force to be reduced to that wheel. This is how ABS prevents tire skid and the accompanying loss of steering control. This improves vehicle safety during heavy brake use or when braking with poor traction.

Although anti-lock braking systems help to prevent wheel lock, you should not expect the stopping distance for your vehicle to be shortened.

Drivers unfamiliar with anti-lock braking may be surprised by the pulsations that they may feel in the brake pedal when they brake hard. Make sure you know what to expect so you will not be distracted by the pulsation or tempted to release the pedal during emergency braking manoeuvres.

Threshold braking — Threshold braking should bring you to a reasonably quick controlled stop in your own lane, even in slippery conditions. This technique is generally practised in a vehicle that is not equipped with ABS. Brake as hard as you can until a wheel begins to lock up, then release pressure on the pedal slightly to release the wheel. Press down on the brake pedal, applying as much braking force as possible without inducing a skid. If you feel any of the wheels begin to lock up, release the brake pressure slightly and re-apply. Don’t pump the brakes. Continue braking this way until you have slowed the vehicle to the desired speed.

Vehicles equipped with ABS should provide controlled braking on slippery surfaces automatically. Press the brake pedal hard and allow the system to control wheel lock-up.