: 1500x1223 px
: July 5, 2018
Testing a battery's performance and reserve (or amp-hour) capacity is not just a matter of seeing whether it will hold a charge (or checking the electric eye found on some batteries to see if it is green), so testing is best done by an auto technician at a repair shop. A professional can also determine if any problems you are having may be caused by something else, like your battery terminals or alternator. If a bad battery is the culprit, your mechanic will help you choose and install an appropriate replacement.
If belt tension is correct, then the next item to check is the alternator itself. You now have two choices - you can test the alternator yourself with a simple test using a voltmeter, or you can have the test performed by a professional. If you choose to do the test yourself, then you will need a DC voltmeter, or a multimeter. Such a unit can be purchased at most auto supply stores, hardware stores, department stores, home improvement stores, etc.