Dodge RAM TRUCK 1500 1995 Service Manual page 198

5 - 21 BEAR WHEEL ANTILOCK BRAKE (RWAL) SYSTEM
B R
REAR W H E E L ANTILOCK BRAKE (RWAL) S Y S T E M
INDE1
page
Antilock Component Serviceability 30
Clearing A Fault Code 29
Combination Valve Operation 28
Control Module Removal/Installation . 31
Diagnostic Fault Flash Codes 29
Fault Code Capacity 29
Fault Code Identification . . . . . . . . . . . . . . . . . . . . 29
Fault Condition Causes 29
General Information . . . . . . . . . . . . . . . . . . . . . . . 26
Rear Speed Sensor Rear Harness Removal/
Installation 33
page
Rear Speed Sensor Removal/I nstallation 32
Rear Wheel Antilock System Diagnosis . . . . . . . . . 29
Rear Wheel Antilock System Operation 28
RWAL Diagnostic Connector 29
RWAL System Brake Bleeding 33
RWAL System Components . 26
RWAL Valve/Combination Installation . . . . . . . . . . . 31
RWAL Valve/Combination Valve Removal . 30
GENERAL INFORMATION
A rear wheel antilock (RWAL) brake system is
standard equipment on all BR models (Fig. 1). The
system is controlled by a separate electronic control
module.
SPEED
SENSOR
ANTILOCK
VALVE
EXCITER
RING
J9305-45
Fig. 1 Rear Wheel Antilock (RWAL) Brake System
The RWAL system retards rear wheel lockup dur­
ing periods of high wheel slip and deceleration. Re­
tarding lockup is accomplished by modulating fluid
pressure to the rear brake units.
Rear brake fluid apply pressure is modulated ac­
cording to wheel speed, degree of wheel slip and rate
of deceleration. A sensor in the rear axle housing con­
verts differential rotating speed into electronic sig­
nals. The signals are transmitted to the electronic
control module for processing. The control module de­
termines rate of deceleration and wheel slip from
these signals.
RWAL SYSTEM COMPONENTS
RWAL system components include:
© electronic control module
• rear brake antilock (RWAL) valve
o speed sensor and exciter ring
® antilock warning lamp
A standard master cylinder and vacuum power
brake booster are used for all applications. All of the
RWAL system hydraulic components are located on
the driver side of the engine compartment (Fig. 2).
MASTER
CYLINDER
ASSEMBLY
RWAL
VALVE J9405-76
Fig. 2 RWAL System Hydraulic Component Location