Conditions for Setting the DTC
WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
C0475 00
The power steering control module detects a short to ground, short to voltage, or an open/high resistance on any of the internal power steering assist motor circuits.
C0475 59
The power steering control module detects the thermal cycle counter has exceeded the maximum allowable limit indicating that the whole steering gear system must be replaced.