Antilock Brakes / Traction Control Systems: Description and Operation

REAR-WHEEL ANTILOCK BRAKE SYSTEM (REAR-WHEEL ABS)
The Sportage is equipped with a rear-wheel antilock brake system (rear-wheel ABS). The ABS control unit senses the drop in rear-wheel speed and modulates hydraulic pressure to the rear brakes, inhibiting lockup.

The rear-wheel ABS is composed of electrical and mechanical components (hydraulic unit), and the components of the standard brake system.

Any malfunction of the ABS electrical or mechanical components is judged by the self-diagnosis function in the ABS control unit. All malfunctions are indicated by the warning lamp in the instrument panel. The location of a malfunction is indicated to the technician by a flashing pattern of the ABS warning lamp. The self-diagnosis and indication functions must be used when diagnosing malfunctions of the ABS.

When the 4WD indicator light is on, the ABS system is designed to deactivate.

Battery power is applied at all times to, the ABS relay from the "ABS" fuse. In addition, when the ignition is ON, power is applied to the ABS relay from the "WIPER" fuse.

When the ignition is turned ON, power is supplied to the ABS control unit through the ABS relay. The ABS control unit monitors/controls the ABS speed sensor, the stop light switch, the brake system warning light, and the 4WD lamp on the instrument cluster. It also controls the isolation and dump solenoid valves in the ABS Hydraulic Unit.