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.
DTC C028A
The parking brake control module detects an internal motor malfunction.
DTC C028B
The parking brake control module detects an internal motor position sensor signal malfunction.
DTC C028F
The parking brake control module detects an internal park brake solenoid malfunction.