Electronic Brake Force Distribution (EBD)

On initial application of the brake pedal, full pressure is applied to the rear brakes. The ABS module uses wheel speed sensor inputs to evaluate rear wheel slip. Once the rear wheel slip exceeds a predetermined threshold, the ABS module commands the HCU to close the appropriate isolation valves to hold the rear brake pressure constant while allowing the front brake pressure to build. This creates a balanced braking condition between the front and rear wheels. If the rear wheel slip continues and exceeds a second predetermined threshold, the ABS module commands the HCU to open the dump valves to decrease the rear brake pressure and allow the rear wheels to recover. A slight bump sensation may be felt in the brake pedal when EBD is active. If the ABS is disabled due to Diagnostic Trouble Codes (DTCs) being present in the ABS module, EBD continues to function unless the Diagnostic Trouble Codes (DTCs) are for wheel speed sensors or the HCU solenoid valves. When EBD is disabled, the ABS warning indicator, the red brake warning indicator and traction control indicator illuminate.