Antilock brake systems, or ABS, are an electronic safety feature added to a vehicle’s normal braking system. They are designed to prevent the vehicle’s wheels from locking up when a driver brakes hard in an emergency situation, to prevent skidding on wet pavement, and to allow the driver to continue steering the vehicle when the brakes are pressed hard. Antilock brakes are standard equipment on most new cars and trucks. They come as four wheel systems or rear wheel only systems; rear wheel systems are usually available only on pickup trucks and SUVs.
If you’ve recently purchased a vehicle that is equipped with antilock brakes, take some time to learn how they work and how to use them to your benefit when driving in potentially hazardous situations. Your owner’s manual can give you tips and information about using your ABS.
Most antilock braking systems are speed activated, which means that the vehicle must be traveling over a certain speed to activate. The system also requires that the brake pedal is pressed firmly and continuously. Normal braking in a non-emergency situation will not activate the ABS.
The most important thing you can do to teach yourself how the antilock brakes work on your vehicle is to practice using them. Choose a large empty parking lot or a completely deserted road on a day with good weather. Begin driving your car and get the speed up to 25 to 30 miles per hour; then firmly step on the brakes. Pay attention to what noises the ABS is making and how the brake pedal responds. Make sure to continue steering while you keep pressure on the brake pedal. Do not pump the brakes; the antilock brakes are designed to automatically pump the brakes for you.
If your antilock brake system switched on during the practice run, the brake pedal may vibrate slightly or pulse under your foot. The pedal may also feel like it’s dropping away from your foot. You may hear scraping or grinding noises. The noises and pedal vibrations are both indicators that the ABS has been activated and is working properly. Once you feel comfortable with the ABS under good weather conditions, you should practice using the brakes after it rains and the pavement is wet.
Many drivers believe that antilock brakes are designed to stop their vehicles in shorter distances than regular brakes. This is true for both wet and dry hard pavement, but on soft surfaces such as gravel or snow, braking distances may be longer using the ABS.
Most vehicle manufacturers do not specify any special maintenance for ABS. However, antilock brake systems wear down brake fluid more quickly than standard brake systems. Due to the expense of replacing some ABS parts, car owners may want to flush their vehicle’s brake system yearly as preventative maintenance using the brake fluid recommended by the manufacturer.