Battery Load Shed
WARNING: This page is about a different car, the 2017 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
The BCM monitors the battery state of charge and when necessary will shut off accessories in order to save the remaining battery charge.
Refer to: Charging System - 3.5L Duratec (209kW/284PS)/5.0L 32V Ti-VCT - System Operation and Component Description .