Auxiliary pump diagnostic systems and methods

摘要

A system includes an auxiliary pump that provides pressurized fluid to a transmission during an engine auto stop/start event. A mechanical pump provides pressurized fluid to a transmission during engine operation after the engine auto stop/start event. An auxiliary pump diagnostic system includes a slip determination module that determines slip of a torque converter based on an engine speed and a transmission input speed. A fault determination module diagnoses a fault in the auxiliary pump in response to an engine auto start and based on the slip of the torque converter.