Keep in mind that you can use a voltmeter to check for voltage and continuity but it will NOT tell you about the load carrying capacity of the main cables. In other words if you have a cable going from the battery to the starter that consists of 40 strands of wire and 39 of those strands are broken, your voltmeter will read the voltage as being OK even tho there is no way that the cable can carry the current necessary to turn over the starter with one strand of wire. A severely corroded cable will usually test fine with a voltmeter but it will not be able to handle the amps that your starter and charging circuits.
