Advanced Emergency Brake Assist

Advanced Emergency Brake Assist (AEBA) improves braking response during emergency braking.

With AEBA, if the risk of a collision increases after the vehicle passes the forward alert activation threshold. The Adaptive Speed Control Module (ASCM) signals the ABS control module to activate the electronic brake prefill and AEBA functions.

With AEBA the electronic brake prefill function operates in 2 stages:

• Stage 1: Applies a brake pressure of approximately 3 bar (43.5 psi) to all of the brakes. Lowers the AEBA activation threshold in the ABS control module. Signals to the Body Control Module/Gateway Module (BCM/GWM) on the High Speed (HS) Controller Area Network (CAN) chassis systems bus. This signal is used to activate the stop lamps.
• Stage 2: Increases the brake pressure to approximately 10 bar (145 psi).

Stage 1 is activated if the collision risk increases to a level considered as credible, with the accelerator pedal pressed.

Stage 2 is activated when the accelerator pedal has already been released when the collision risk increases to the credible level. The 2 stages of electronic brake prefill are activated simultaneously, to give an immediate brake pressure of 10 bar (145 psi). While the second stage of electronic brake prefill is active, if the brake pedal is then pressed quickly the ABS control module activates AEBA. Even if only light pressure is applied to the pedal.

AEBA is available at vehicle speeds above 7 km/h (5 mph) and will function even when forward alert and adaptive speed control are switched off.

If a fault occurs in the system, a related message is displayed in the message center. AEBA will not be available until the fault is rectified.