Controller Antilock Brake (CAB)

Controller - Antilock Brake (CAB)

The anti lock brake controller (CAB) is a microprocessor-based device that monitors wheel speeds and controls the antilock functions.

The primary functions of the CAB are:
monitor wheel speeds
detect wheel locking tendencies
control fluid pressure modulation to the brakes during antilock stop operation
monitor the system for proper operation
provide communication to the DRB while in diagnostic mode
store diagnostic information in non-volatile memory

The CAB continuously monitors the speed of each wheel. When a wheel locking tendency is detected, the CAB will command the appropriate valve to modulate brake fluid pressure in its hydraulic unit. Brake pedal position is maintained during an antilock stop by being a closed system with the use of 3 accumulators.
The CAB continues to control pressure in individual hydraulic circuits until a wheel locking tendency is no longer present. The CAB turns on the pump/motor during an antilock stop.
The antilock brake system is constantly monitored by the CAB for proper operation. If the CAB detects a system malfunction, it can disable the antilock system and turn on the antilock warning lamp. If the antilock function is disabled, the system will revert to standard base brake system operation.

The CAB inputs include the following:
four wheel speed sensors
stop lamp switch
ignition switch
main relay voltage
pump/motor relay output
diagnostic communication ISO/K
G switch (acceleration switch)

The CAB outputs include the following:
six valve/solenoid drivers
main relay actuation
pump/motor relay actuation
ABS warning lamp actuation diagnostic communication