A system and method is provided for evaluating performance of a supply circuit for electric vehicle charging. An electrical connection is established between a vehicle circuit and a supply circuit for an external Alternating Current (AC) power supply. The electrical connection includes a hot, neutral, and ground conductor. A control signal is transmitted to activate a switch disposed along the electrical connection for selectively initiating vehicle charging. Input signals are received including: a line current signal indicative of a current along at least one of the hot conductor and the neutral conductor, and at least one of a line voltage signal and a neutral voltage signal. The line voltage signal being indicative of a voltage potential between the hot conductor and the neutral conductor. The neutral voltage signal being indicative of a voltage potential between the neutral conductor and the ground conductor. At least one of the input signals is compared to predetermined resistance data for evaluating supply circuit performance.