A pre-charging system for a capacitor in a voltage inverter for an electric motor is provided. The system includes a grounding contactor electrically coupled between a grounding terminal of a battery pack and a first end of the capacitor. The system further includes a pre-charging contactor and a resistor electrically coupled in series. The pre-charging contactor and the resistor are electrically coupled between a high voltage terminal of the battery pack and a second end of the capacitor. The microprocessor determines a total amount of energy supplied to the resistor and induces the pre-charging contactor to have an open operational position to electrically de-couple the high voltage terminal from the second end of the capacitor, if the total amount of energy is greater than a threshold amount of energy.