Conditions for Setting the DTC
WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
C0455 09 or C0455 19
The EBCM detects an internal sensor failure.
C0455 39 or C0455 5A
The EBCM detects a short to voltage, short to ground or an open/high resistance on one of the steering angle sensor circuits.