Circuit/System Description
WARNING: This page is about a different car, the 2007 Pontiac G5 Pursuit, 2007 Pontiac G5, and 2007 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
The electronic brake control module (EBCM) monitors the battery voltage level available for system operation. A low voltage condition prevents the system from operating properly.