Kia Carens. Manual — part 221

Brake System

ABS(Anti-Lock Brake System)

Brake System

2001 > 1.8L DOHC >

Wire harness diagram structure

2001 > 1.8L DOHC >

Description and operation

Anti-lock brake system (ABS)

The anti-lock brake system (ABS) is designed for prevents wheels from locking due to excessive brake efforts.
Main functions of the ABS are;

• To reduce braking distance by avoiding wheels from locking.
• To improve stability of steering and handling by avoiding slip during braking.

Type of 4-sensors and 3 channel is introduced so that front wheels control each wheel independently and rear wheels
control by type of select low (controlling hydraulic pressure on side on which slip is first occurred.)

ABS control unit

The ABS control unit performs the following functions.

• Controls the ABS
• Calculates vehicle speed
• Self-diagnostics: Stores malfunction codes, performs ABS control unit self-diagnostic and fail-safe functions with two

separated microprocessors.

1. The ABS control unit continuously checks locking of each wheel and controls each valve to adjust brake fluid pressure

ifrequired. The ABS control unit also checks that components are working properly and stops ABS if a malfunction is
detected.
Then, it is operated as a standard brake system.

Speed sensor (structure)

1. The speed sensor detects wheel rotation and consists of a permanent magnet and pickup coil. Sensors for the front

wheelsare attached to drive shaft and rear hub spindle for the rear wheel.

ABS warning lamp

1. The ABS warning lamp in the instrument panel illuminates for 3 seconds after ignition key is turned ON. If the warning

lamp does not turned off,or turns on intermittently, there is a malfunction in ABS. When a malfunctionof ABS is occurs,
the ABS will not operate and the brakes will operate as a standard brake system.

Hydraulic control unit (HCU)

1. The HCU consists of a motor pump assembly in which motor sensor is built, and valve block for controlling ABS

pressure.
Motor sensor is built in motor, and output signal, which detects condition of a motor pump assembly, is sent to ABS
control unit.

Reference
Diameter of front brake pipe holepitch: FL, RL: 0.47 in (12 mm)
Diameter of rear brake pipe holepitch: FR, RR: 0.39 in (10 mm)

The motor pump is a reciprocal 2-line pump and transmits enough pressure to the wheel system, and the valve block
controls fluid pressure to each wheel cylinder.

ABS module

The ABS module illuminates the ABS warning lamp when an ABS failure occurs.

Type of operation

Under normal conditions, the standard brake system performs until locking of a wheel is detected by the ABS control unit.