DTC C0561 71, 72, 74, and 75
WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The EBCM receives an invalid serial data message/signal from another module which causes the EBCM to deactivate the antilock brake system, traction control and the vehicle stability enhancement system.