Vehicle electrical system management systems and methods are provided for a vehicle, such as a tractor/trailer. In particular, a system and method are provided for detecting a faulty alternator or other motorized component by analyzing the waveform of the alternator and other motor of the vehicle. As a result, the system and method can provide a motorist with an advance warning as whether the alternator or other motor is functioning improperly. In addition, a system and method are provided for controlling the charging of a battery based upon the temperature of the battery such that the battery can be charged in a more efficient manner. In this regard, the temperature of the battery is sensed and the alternator thereafter charges the battery to a predefined voltage based upon the sensed temperature and a predetermined battery temperature/battery voltage schedule.