Next, turn on the head lights so current is trying to flow, then measure the battery's voltage again, right on the posts if you have top posts, otherwise, you'll have to skip right to the side post bolt heads. Please tell me what you find for voltage. If you have top posts, now move the meter probes to the cable clamps and measure again. You should find exactly the same voltage.
If you have side posts, we'll have to skip over part of the tests and go right to the starter. Put one meter probe right on the large stud on the starter that the battery cable is bolted to, and the other meter probe on an unpainted surface on the engine block. You'll find full battery voltage at first, but I'm interested in the voltage you find when a helper tries to crank the engine. During normal cranking, that voltage must stay above 9.6 volts. When you have a cable or connection problem, you're going to find considerably lower voltage.
Another clue to a bad cable or connection is the head lights or interior lights will get real dim during cranking.
Sunday, September 13th, 2015 AT 8:36 PM