Anti-Lock Brake System: Description
NOTE:
For traction control systems, see TRACTION CONTROL article.
The Anti-Lock Brake System (ABS) consists of hydraulic unit, brake actuator, actuator solenoids, lateral acceleration sensor, pump motor, ABS Electronic Control Unit (ECU), indicator light, and 4 wheel speed sensors. See Fig 1.
An ABS indicator light, located in the instrument cluster, comes on for 3 seconds as a bulb test when ignition is first turned on. A primary check is performed after each engine start and initial time vehicle speed exceeds 6 MPH. An actuator noise is heard during this period of time. This is normal.
NOTE:
For additional information on brake system, see BRAKE SYSTEM RWD article.