The simplest test of a battery's health is to see what voltage it is currently supplying. To do this set your multimeter on the voltage setting with the scale set to about 20 volts and connect the leads to the positive and negative terminals of the battery. A fully charged battery should show a reading of about 12.6 volts or higher.

Battery won't charge

This topic covers information about charging a battery from an outboard motor and problems that can cause your battery to stop charging.