Conditions for Setting the DTC
WARNING: This page is about a different car, the 2016 Buick LaCrosse. However, it is still accessible from the selected car via links, so may be relevant.
P0A88
14 volt power module input current is Less than 0.5 amp for greater than 2 seconds.
P0A89
14 volt power module input current is greater than 22.5 amps for greater than 2 seconds.