EXPANSION TANK CAP; A7. A cover that prevents foreign debris from entering the container. Cap for the Hybrid Inverter Coolant Reservoir. Includes: Expansion Tank Cap Seal. Location-Auxiliary Reservoir. Location-Primary Reservoir. Location-Reservoir. Radiator Cap. To 09/30/2013. Cover. Drive Motor Inverter Coolant. Engine Coolant. Expansion Tank. Radiator. Included with: Reservoir.