Vehicle batteries are fully charged at 12.7 volts. They can read a little higher if they have been recently charged. The first step on a maintenance free battery is checking the eye on the battery to see if it is green. If it is clear or black, your battery is not healthy. The second step is to check it's voltage. You can do this with a voltmeter or a multi-meter. Put the red lead to the positive post and the black lead to the negative post on the battery. (On most multi-mete