Electric Auxiliary Pump Drive Motor Assembly
WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The electric auxiliary pump drive motor is driven by a 12V AC motor controlled by a dedicated auxiliary fluid pump control module that is mounted in the engine compartment. Control of the auxiliary pump drive motor is managed by the HPCM, which communicates directly with the auxiliary fluid pump control module. The purpose of the auxiliary pump drive motor is to supply oil to the transmission for lube, cooling and clutch application during Auto-stop when the engine is off and the main transmission pump is not operating. The auxiliary pump drive motor is commanded on when propulsion is active, such as when the vehicle is in electric only or stopped at a traffic light.