2013 BMW ActiveHybrid 3 Submodel: Base; Engine: 3.0L L6; Engine Cooling;. 2014 BMW ActiveHybrid 3 Submodel: Base; Engine: 3.0L L6; Engine Cooling; Location: Expansion Tank;. 2015 BMW ActiveHybrid 3 Submodel: Base; Engine: 3.0L L6; Engine Cooling; Location: Reservoir;.