Circuit/System Description
WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
The electronic brake control module (EBCM) monitors the 12V system voltage to make sure that the voltage stays within the proper range. Damage to components, and incorrect data input can occur when the voltage is out of range. If the EBCM detects a system voltage less than the normal range, the EBCM will set DTC C0899 and the ECM will set DTC C12E1.