Conditions for Setting the DTC
WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
Accessory DC power control module 42 volt circuit is more than 50 V for more than 3 seconds.