An on-board battery charging system for a plug-in electric vehicle has a charging unit for charging a high-voltage battery and a controller for controlling and managing current flow used to support charging related operations for the high-voltage battery. The controller may detect a connection between the on-board battery charging system and electric vehicle supply equipment (EVSE) and is configured to enter a sleep mode when a control pilot signal from the EVSE is either absent or indicative of a delayed charge mode. The charging system may include a wake-by-control pilot circuit operable to wake the controller from the sleep mode when the control pilot signal is detected and when the control pilot signal transitions from a non-zero static DC voltage to an active PWM signal.