Chrysler Stratus RHD 1997 Interactive Electronic Service Manual page 177

WINDSHIELD HOOD PROP ROD FLUID BOTTLE AIR CONDITION- WASHER ING HOSE CONTROLLER
5 - 82 BRAKES
DESCRIPTION AND OPERATION (Continued)
CONTROLLER ANTILOCK BRAKES (CAB)
The Antilock Brake Controller (CAB) is a micropro-
cessor based device which monitors the ABS system
during normal braking and controls it when in an
ABS stop. The CAB is mounted in the right front cor-
ner of the engine compartment using an integral
mounting bracket to attach it to the inner fender
(Fig. 7). The CAB uses a 60 way electrical connector
on the vehicle wiring harness. The power source for
the CAB is through the ignition switch in the Run or
On position. THE CONTROLLER ANTILOCK
BRAKE (CAB) IS NOT ON THE CCD BUS
Fig. 7 Location Of Controller Antilock Brake
The primary functions of the (CAB) are:
(1) Detect wheel locking tendencies.
(2) Control fluid modulation to the brakes while in
ABS mode.
(3) Monitor the system for proper operation.
(4) Provide communication to the DRB scan tool
while in diagnostic mode.
The CAB continuously monitors the speed of each
wheel through the signals generated at the Wheel
Speed Sensors to determine if any wheel is beginning
to lock. When a wheel locking tendency is detected,
the CAB commands the HCU to modulate brake fluid
pressure in some or all of the hydraulic circuits. The
CAB continues to control pressure in individual
hydraulic circuits until a locking tendency is no
longer present.
The ABS system is constantly monitored by the
CAB for proper operation. If the CAB detects a fault,
it will turn on the Amber ABS Warning Lamp and
disable the ABS braking system. The normal Non
ABS braking system will remain operational.
The CAB contains a self-diagnostic program which
will turn on the Amber ABS Warning Lamp when a
ABS system fault is detected. Faults are then stored
in a diagnostic program memory. There are multiple
fault messages which may be stored in the CAB and
displayed through the DRB scan tool. These fault
ANTILOCK BRAKES TRICAL 60–WAY NECTOR ELEC- CON-
messages will remain in the CAB memory even after
the ignition has been turned off. The fault messages
can be cleared by using the DRB scan tool, or they
will be automatically cleared from the memory after
a minimum of 3500 vehicle miles are accumulated.
CONTROLLER ANTILOCK BRAKE INPUTS
• Four wheel speed sensors.
• Stop lamp switch.
• Ignition switch.
• System relay voltage.
• Ground.
• Pump/Motor Relay Monitor
• Diagnostics Communications
CONTROLLER ANTILOCK BRAKE OUTPUTS
• 4 Decay Solenoids
• ABS warning lamp.
• System relay actuation.
• Diagnostic communication. (Single line ISOK)
• Pump motor relay actuation
• Brake Lamp (Low Fluid/Pressure).
ABS AMBER WARNING LAMP FUNCTION AND
LOCATION
The ABS system uses an Amber ABS Warning
Lamp, located in the instrument cluster. The purpose
of the warning lamp is discussed in detail below.
The ABS warning lamp will turn on when the CAB
detects a condition which results in a shutdown of
ABS function. The ABS Warning Lamp is normally
on until the CAB completes its self tests and turns
the lamp off (approximately 4-5 seconds after the
ignition switch is turned on). When the ABS warning
lamp is on, only the ABS function of the brake sys-
tem if affected. The standard brake system and the
ability to stop the car will not be affected when only
the ABS warning lamp is on.
NOTE: When the CAB detects a non-functional
Amber ABS Warning and a ABS fault is also
detected at the same time which results in shutting
down the ABS Brakes, then the CAB will turn on the
Red Brake Warning Lamp.
ABS BRAKING MODE HYDRAULIC CIRCUIT
SOLENOID AND VALVE FUNCTION
Through the following operation descriptions the
function of the various hydraulic control valves in the
ABS system will be described. The fluid control
valves mentioned below, control the flow of pressur-
ized brake fluid to the wheel brakes during the dif-
ferent modes of ABS braking.
For explanation purposes we will assume all speed
sensors are sending the same wheel speed informa-
JA