Anti-Lock Brake System: Description

Anti-Lock Brake System (ABS) consists of an ABS Electronic Control Unit (ECU), ABS solenoid relay, motor relay, actuator and 4 speed sensors. See Fig 1.

An ABS indicator light is located on the instrument panel. This light illuminates for 3 seconds as a bulb test when ignition is first turned on. A primary check is performed after each engine start, and ABS system begins to operate when vehicle speed exceeds 6 MPH. You may hear a sound in the engine compartment for a few seconds when engine is first started or when first accelerating. This means ABS is performing a system self-diagnosis and does not indicate a problem.

Fig 1: Locating ABS Components

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