Anti-Lock Brake System - Honda Prelude 1993 Service Manual

Hide thumbs Also See for Prelude 1993:

Table of Contents

Anti-lock Brake System (ABSI

Features/Construction/Operation

In a conventional brake system, iJ the brake pedal is depressed very hard, the wheels can lock before the vehicle comes

to a stop. In such a case, the stability of the vehicle is reduced if the rear wheels are locked, and maneuverability of the

vehicle is reduced if the front wheels are locked, creating an ext.emely unstable condition.

The Anti-lock Brake System (ABS) modulates the pressure of the brake tluid applied to each front caliper or both rear

calipers thereby preventing the locking of the wheels, whenever the wheels are likely to be locked due to hard bfaking. lt

then restores normal hydraulic pressure when there is no longer any possibility of wheel locking.

a Increased braking stability can be achieved regardless of changing d.iving conditions.

a The maneuverability ot the vehicle is improved as the system prevents the front wheels from locking.

a When the anti-lock b.ake system goes into action, a kickback is felt on the brake pedal.

a The system is equipped with a self-diagnosis function. When an abnormality is detected. the ABS indicator light

comes on. The location oi the system's trouble can be diagnosed from the frequency of the system indicator light

This sYstem has individual control ot the lront wheels and common control ("Select Low") lor the rear wheels.

"Select Low"

means that the rear wheel that would lock first (the one with the lowest resistance to lock-uo)

determines anti-lock brake system activation tor both rear wheels.

The system has a fail-safe function that allows normal braking if there's a problem with the anti-lock brake

Construction

In addition to the conventional b.aking system, the anti-lock brake system consists of: gear pulsers attached to the

rotating part of individual wheels; wheel sensors, which generate pulse signals corresponding to the revolution of the

gear pulsers; ABS control unit, which controls the working of the anti-lock brake system by performing calculations bas-

ed on the signals from the individual wheel sensors and the individual switches; modulator unit, which adjusts the

hydtaulic pressure applied to each caliper on the basis ot the signals received from the ABS control unit; an accumulator,

in which high-pressure brake lluid is stored, a pressure switch, which detects the pressure in the accumulator and

transmits signals to the ABS control unit; a power unit, which supplies the high-pressure working fluid to the ac-

cumulator by means of a pump; a motor relay Ior driving the power unit; {ail-saie relays. which cut off the solenoid valve

ground circuit when the fail-safe device is at work; and, an ABS indicator light.

MASTER CYLINDER

WHEEL SENSOR

PULSER SENSOR

Troubleshooting