: 1000x1121 px
: June 23, 2018
If the battery terminals are clean and tight, then the next item to check is drive belt tension. If the belt which drives the alternator is too loose, then the alternator will not produce enough electrical current to keep up with demand. Many modern vehicles utilize a single belt which drives the alternator and other accessories. This system usually also has an automatic belt tensioner which always maintains correct tension and is not adjustable. If your vehicle uses a wide, multigrooved or so-called "Serpentine" belt to drive the alternator, then it likely also has an automatic tensioning device.
A good thing with battery checking and trouble shooting is that you need very little technical equipment. All you need is a good, old Digital Volt Ohm Meter and a charger for the battery. Each auto battery manufacturer uses a certain color in the battery 'eye' which tells whether a charge is needed. This is a fast and easy way to alert you for re-charging. Check out your battery manufacturer's specification of the 'eye' and everything associated with it.