Anti Lock Brake Safety Information (ABS)

GeneralAutoRepair

An anti-lock braking system, or ABS (from the German, Antiblockiersystem) is a safety system which prevents the wheels on a motor vehicle from locking while braking.

A rotating road wheel allows the driver to maintain steering control under heavy braking by preventing a skid and allowing the wheel to continue interacting tractively with the road surface as directed by driver steering inputs. While ABS offers improved vehicle control in some circumstances, it can also present disadvantages including increased braking distance on slippery surfaces such as ice, packed snow, gravel, steel plates and bridges, or anything other than dry pavement. ABS has also been demonstrated to create a false sense of security in drivers, who may drive more aggressively as a result.[citation needed]

Since initial widespread use in production cars, anti-lock braking systems have evolved considerably. Recent versions not only prevent wheel lock under braking, but also electronically control the front-to-rear brake bias. This function, depending on its specific capabilities and implementation, is known as electronic brakeforce distribution (EBD), traction control system (TCS or ASR), emergency brake assist (BA, EBA or HBA), or electronic stability control (ESP, ESC or DSC). Wikipedia:ABS

This ABS brake safety article is intended for general information purposes only. This information may not apply to all makes and models. If vehicle is equipped with Anti-Lock Brake System (ABS), refer to appropriate ABS article in the brakes section for description, operation, depressurizing, testing, system bleeding, trouble shooting and servicing of specific system.

CAUTION: Failure to depressurize ABS could lead to physical injury.

• Never open a bleeder valve or loosen a hydraulic line while ABS is pressurized.
• Never disconnect or reconnect any electrical connectors while ignition is on. Damage to ABS control unit may result.
• Don't attempt to bleed hydraulic system without first referring to the appropriate ANTI-LOCK BRAKE SYSTEM article in the BRAKES section.
• Only use specially designed brake hoses/lines on ABS equipped vehicles.
• Don't tap on speed sensor components (sensor, sensor rings). Sensor rings must be pressed into hubs, NOT hammered into hubs. Striking these components can cause demagnetization or a loss of polarization, affecting the accuracy of the speed signal returning to the ABS control unit.
• Don't mix tire sizes. Increasing the width, as long as tires remain close to the original diameter, is acceptable. Rolling diameter must be identical for all 4 tires. Some manufacturers recommend tires of the same brand, style and type. Failure to follow this precaution may cause inaccurate wheel speed readings.
• Don't contaminate speed sensor components with grease. Only use recommended coating, when system calls for an anti-corrosion coating.
• When speed sensor components have been removed, ALWAYS check sensor-to-ring air gaps when applicable. These specifications can be found in each appropriate article.
• Only use recommended brake fluids. DO NOT use silicone brake fluids in an ABS equipped vehicle.
• When installing transmission devices (CB's, telephones, etc.) on ABS equipped vehicles, DO NOT locate the antenna near the ABS control unit (or any control unit).
• Disconnect all on-board computers, when using electric welding equipment.
• Don't expose the ABS control unit to prolonged periods of high heat (185 °F/85°C for 2 hours is generally considered a maximum limit).

WARNING: Take care not to breath in brake dust. Brake dust is filled with asbestos which causes mesothelioma cancer and or tumor. Mesothelioma destroys tissue and organs and have the potential to spread to other parts of the body. Always clean brake parts with a certified brake parts cleaner before working on the brake system. This will reduce the amount of exposure to asbestos.

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