Alb Description Features/Construction/Operation - Honda Acura NSX 1991 Service Manual

ALB Description
Features/Construction/Operation
General
In a conventional brake system, if the brake pedal is depressed excessively, 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 maneuverabily of
the vehicle is reduced if the front wheels are locked, creating an extremely unstable condition.
The Anti-Lock Brake system modulates the pressure of the brake fluid applied to each caliper, thereby preventing the
locking of the wheels, whenever the wheels are likely to be locked due to excessive braking. It then restores normal
hydraulic pressure when there is no longer any possibility of wheel locking.
4 Channel Anti-Lock Brake system Features
l
The maneuverability of the vehicle is improved as the system prevents the front wheels from locking.
l When the anti-lock brake system goes into action, kick-back is felt on the brake pedal.
indicator light comes on.
The location of the system's trouble can be diagnosed from the frequency of the system indicator light display blinks.
Braking force is controlled on each of the four wheels independently, resulting in optimum braking efects
wheels.
The system has a fail-safe function that allows normal braking if there's a problem with the anti-lock brake system.
Items
Gear Pulser
Control Unit
Modulator Solenoid
Unit
Service Check Connector
System Control Methord
with PCV function
(Prooortionina Control
Construction
In addition to the conventional braking system, the anti-lock brake system is composed of: gear pulsers attached to the
rotating part of individual wheels; speed sensors, which generate pulse signals in correspondence to the revolution of the
gear pulsers; control unit, which controls the working of the anti-lock brake system by performing calculations based on
the signals from the individual speed sensors and the individual switches; modulator unit, which adjusts the hydraulic
pressure applied to each caliper on the basis of the signals received from the control unit; an accumulator, in which high-
pressure brake fluid is stored; a pressure switch, which detects the pressure in the accumulator and transmits signals to
the control unit; a power unit, which supplies the high-pressure working fluid to the accumulator by means of a pump; a
motor relay for driving the power unit; a fail-safe relay, which cuts off the solenoid valve ground circuit when the fail-safe
device is at work; and, an anti-lock brake system indicator light.
19-28
3 Channel
Front: 50
Rear: 50
12 and 18 pins
4 Pistons
3 Solenoid Valves
Front wheels controlled
independently.
Rear wheels controlled commonlv
Yes
Valve)
on the four
4 Channel
Front: 47
Rear: 50
18 and 20 pins
4 Pistons
4 Solenoid Valves
Four wheels controlled
independently.
No