Circuit/System Description
WARNING: This page is about a different car, the 2017 GMC Canyon and 2017 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.
The radio communicates with the radio controls via serial data. This DTC indicates a fault in the radio controls. No external circuits are involved. The radio may continue to respond normally to faceplate functions when this DTC is set.