The IMA system is controlled by the Power Control Unit (PCU), which is located under the cargo-area floor, along with the battery pack, high-voltage inverter, DC to DC converter, Electronic Control Unit (ECU) and two cooling fans. The PCU controls the flow of electricity between the IMA motor and battery pack, supplying energy to the assist motor when needed, and it also regulates the system's nickel-metal hydride batteries and controls the idle-stop feature.
Electrical power for the IMA system is produced by the IMA motor during regenerative braking and when cruising, and is stored in a bank of nickel-metal hydride batteries. Since the motor's power consumption when it is assisting is not as great as that of a full-time drive motor, the battery pack is also smaller and lighter. The pack consists of 120 D-sized batteries with a total output of 144 volts and 6.5 amp-hours.