ABS

  
History
How it works
Effectiveness
Components
Q&A


Anti-lock braking system

An anti-lock braking system (ABS) is a system on motor vehicles which prevents the wheels from locking while braking. The purpose of this is to allow the driver to maintain steering control under heavy braking and, in some situations, to shorten braking distances (by allowing the driver to hit the brake fully without the fear of skidding or loss of control). Disadvantages of the system include increased braking distances under certain conditions and the creation of a "false sense of security" among drivers who do not understand the operation and limitations of ABS. ABS has made considerable progress. Recent versions not only handle the ABS function itself (i.e. preventing wheel locking) but also traction control, brake assist, and electronic stability control, amongst others.


Warning Signs

Brake Lights Brake Lights
Emergency brake is on or you have a serious drop in hydraulic pressure. Your brakes may be near total failure.

Drag Drag
Sticking brakes, hot wheels or engine that seems to have lost power. Brakes may be failing to release; the condition can reverse itself, leaving you with no brakes at all.

Grabs Grabs
"Touchy" brakes that grab with the least pressure. May indicate a problem as simple as grease or oil contaminated lining - or as serious as a loose or broken components ready to fail in an emergency.

Hard Pedal Hard Pedal
Requires extreme pressure to make brake function. Can indicate power brake trouble, restricted hydraulic lines, frozen calipers or wheel cylinders, or damaged brake linings.

Low Pedal Low Pedal
Pedal nearly touches floorboard before brakes function. May activate your brake warning light. Problems may require a simple adjustment or indicate something much more serious.

Pull Pull
Car pulls to one side when brakes are applied. May be an under inflated tire, misadjusted brakes or brakes are in need of repair.

Squeal Squeal
Brakes should operate with a minimal amount of noise. Some noise is normal but excessive squeal, screech, grinding, groaning, chatter, clatter or bang means your brakes need attention.

Vibration Vibration
Brake pedal, steering wheel or entire vehicle shakes, vibrates or pulsates when brake is applied. May indicate need to resurface disc brake rotors - or signal a serious problem of a loose component or faulty steering mechanism.