On-board hybrid transmission auxiliary-pump priming control system

摘要

A method and article of manufacture is provided to control an automatic transmission which includes a hydraulic fluid circuit having an electrically-driven auxiliary hydraulic pressure pump. It includes determining the internal combustion engine is shut off during vehicle operation, and monitoring fluidic pressure at a plurality of locations in the hydraulic circuit. Operation of the electrically-driven auxiliary hydraulic pressure pump is commanded to an elevated voltage level when the engine is shut off and the fluidic pressures fail to register substantially proper pressure levels. It includes discontinuing operation of the electrically-driven auxiliary hydraulic pressure pump when the engine is subsequently commanded on, or when an elapsed measure of time has passed, or when the monitored fluidic pressures register substantially proper pressure levels.