Anti-Lock Brakes - Hybrid

Principles of Operation

NOTE: The anti-lock brake system (ABS) module is part of the hydraulic control unit (HCU) and cannot be installed separately.

The ABS module controls the foundation brake function as well as anti-lock braking.

When the ignition switch is placed in the RUN position, the module carries out a preliminary electrical check. At approximately 20 km/h (12 mph), the hydraulic pump motor is turned on for approximately 0.5 second. Any malfunction of the ABS disables the ABS and the anti-lock brake warning indicator illuminates. However, the power-assist braking system still functions normally.

Electronic Brake Distribution
The electronic brake distribution controls the front and rear brake hydraulic pressure and acts as an electronic proportioning valve. It is controlled by the ABS module. When the electronic brake distribution is disabled, the yellow ABS warning indicator illuminates.

Sensor Cluster (Accelerometer)
The sensor cluster (also called the accelerometer) consists of the longitudinal accelerometer. The longitudinal accelerometer measures the acceleration corresponding to the force involved when the vehicle moves forward and rearward in the horizontal plane, along the centerline of the vehicles front and rear wheels.