Method and apparatus for testing a vehicle charge storage system

An apparatus for testing a specific gravity of a battery in a vehicle, said apparatus comprising:

• a measurement circuit for measuring a terminal voltage of a battery in the vehicle, said circuit providing an output which varies in linear relation to the terminal voltage of the battery within an expected range of voltages, wherein said output is provided only when the terminal voltage of the battery exceeds a threshold level;
• a display circuit for indicating the specific gravity of the battery based on the terminal voltage of the battery, said display circuit being electrically connected to the output of the measurement circuit;
• and
• means for electrically connecting said measurement circuit to the battery.

A method for testing a charge storage system in a vehicle, said method comprising:

• electrically connecting a test meter to a battery in the vehicle, wherein said test meter includes a display having at least one scale for displaying at least one charge storage system operating condition, and a measuring circuit which provides an output that varies in linear relation to a terminal voltage of the battery within an expected range of voltages, wherein said output is provided only when the terminal voltage of the battery exceeds a threshold level;
• measuring the terminal voltage of the battery using said test meter;
• determining at least one charge storage system operating condition based on the terminal voltage of the battery;
• and
• displaying said at least one charge storage system operating condition on said at least one scale.