What you should know about...Anti-lock Braking Systems
ABS ... What is it?
ABS is an abbreviation for Anti-lock Braking System. It was designed to help the driver maintain some steering ability and avoid skidding while braking.
ABS was introduced in the mid -1980s and has become "standard" equipment on the majority of vehicles sold in Canada. ABS in cars and most Multi-purpose Vehicles (MPVs) works on all four wheels. This promotes directional stability and allows steering while maximizing braking.
The ABS in most pick-up trucks works only on the rear wheels, which promotes directional stability only. However, there are some available with ABS on all four wheels.
Anti-lock Braking systems were developed to reduce skidding and maintain steering control when brakes are used in an emergency situation.
However, cars with anti-lock brakes are up to 65% more likely to be in fatal crashes than cars without them, says a new US study. It appears that the problem isn't with the technology, it's poor driving habits and lack of driver awareness on how the brakes operate. Driver who rely on technology instead of better driving habits to improve safety are driving down a dangerous road.
Since much of the problem stems from lack of awareness of how to use the brakes, education is needed. Here are Manitoba Safety Council tips on operating ABS-equipped cars:
|In an emergency situation, apply your brakes hard and stay on them. The more pedal chatter the better.|
|Don't pump your brakes. Pumping is for standard brakes. It completely robs ABS brakes of their effectiveness.|
|Remember that ABS brakes do not help you stop quicker under most conditions. They do help you maintain steering control during braking so you can veer around obstacles.|
|The general rule of thumb is that if you have to avoid an obstacle, veer to the right. This way, you avoid oncoming traffic.|
|Don't become an over-confident driver because you have ABS. Drive prudently as you always should.|
Anti-lock brakes are designed to keep cars from going into a skid when the brakes are applied in an emergency. Designed to allow the driver steering control, ABS brakes work by automatically actuating the brakes on and off during emergency stops. They are effective in helping drivers avoid accidents. In certain situations, ABS brakes can help to shorten stopping distances.
Control under heavy braking
ABS allows you to maintain control of the vehicle. Since four-wheel ABS prevents all wheels from skidding, it allows you to steer the vehicle and still maintain braking.
How does it work?
ABS uses wheel speed sensors to determine if one or more wheels are trying to lock up during braking. If a wheel tries to lock up, a series of hydraulic valves limit or reduce the braking on that wheel. This prevents skidding and allows you to maintain steering control
How do I use ABS?
Apply steady and constant pressure - do not take your foot off the brake pedal until the vehicle has stopped and do not pump the brake.
What is that noise and vibration?
This is normal and indicates that the ABS is active. Various ABS sound or feel differently. Some of the effects, for example are:
|a groaning noise|
|a rapid pulsing of the brake pedal|
|a periodic dropping of the brake pedal|
|a hard (non compliant) brake pedal|
|a light that turns on to say "low traction".|
You should familiarize yourself with how your system functions by first reading the "Owners Manual" and then testing your ABS in an empty parking lot under various climatic conditions i.e. dry, wet, snow and ice.
|Brake pedal will
As the ABS engages, you may feel the brake pedal pulsating. This is caused by the system applying and releasing pressure to the brakes.
The noise associated with ABS when it is functioning should not be confused with brake squeal. If your brakes squeal under normal braking, this may mean the brake pads are worn and need replacing. A pulsing brake pedal every time you apply the brakes may mean warped brake rotors and/or seized brake calipers that require servicing.
Is the stopping distance shorter with ABS?
No! From early commercials, it may have looked like you could stop on a dime. That instantaneous stop is not realistic. When braking on dry or wet roads your stopping distance will be about the same as with conventional brakes.
You should allow for a longer stopping distance with ABS than for conventional brakes when driving on gravel, slush, and snow. This is because the rotating tire will stay on top of this low traction road surface covering, and effectively "float" on this boundary layer.
A non ABS braked vehicle can lock its tires and create a snow plow effect in front of the tires which helps slow the vehicle. These locked tires can often find more traction below this boundary layer.
My ABS light comes on. What should I do?
When you start your vehicle an ABS indicator light will illuminate on the instrument panel for a few seconds. This is normal.
My ABS light stays on. What should I do?
This means the ABS is not working. However, the conventional braking system is working. We recommend that you take your vehicle to your nearest dealer for servicing as soon as possible.
My ABS light and my brake warning light both stay on. What should I do?
DO NOT DRIVE THIS VEHICLE! You have no brakes. Have it towed to your nearest dealer.
Road surfaces and ABS
Road hazards that will cause the ABS to function unexpectedly are gravel, sand, ice, snow, mud, railway tracks, potholes, manhole covers, and even road markings when it is raining.
The ABS cannot make up for road conditions or bad judgment. It is still the drivers responsibility to drive at reasonable speeds for weather and traffic conditions. Always leave a margin of safety.