Electric Brake Booster (EBB)
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
When the brake pedal is applied, the cruise control deactivator switch, integrated in the EBB switch, opens and removes the ground signal from the PCM input circuit releasing the throttle, immediately deactivating the cruise control system. For additional EBB information, Refer to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description .