Circuit/System Description
WARNING: This page is about a different car, the 2010 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) monitors the brake pedal position sensor and sends a serial data message when the brake pedal is applied. When the vehicle is stopping, the electronic brake control module (EBCM) monitors for the brake pedal applied serial data message from the BCM, with the brake pressure increasing and the vehicle slowing down, or when the vehicle is accelerating, the brake pedal is not applied and brake pressure is not increasing.