A method for detecting a fault in a battery charger circuit of a vehicle includes determining, based on at least one expected voltage value of an incoming alternating current source, a first threshold. The method also includes measuring at least one line voltage value associated with the incoming alternating current source that provides power to the battery charger circuit. The method also includes determining whether the measured at least one line voltage value is greater than the first threshold. The method also includes in response to a determination that the measured at least one line voltage value is greater than the first threshold, disconnecting the battery charger circuit from and/or preventing the battery charger circuit from connecting to the incoming alternating current source after a first predetermined period.