Ask yourself these questions to diagnose potential issues:

1. 1. Are the terminals fully connected?
   2. Are there any bumps or bulges in the plastic housing?
   3. Is the battery leaking?
   4. Is a terminal broken or melted?
   5. Is there a large build-up of dirt or corrosion on the top of the battery?
   6. Is the battery giving off heat (even when the system is turned off)?

If the battery is a wet-cell (flooded) battery, make sure the water level is maintained with distilled water. If the terminals are loose or disconnected, simply reconnecting them should fix the issue. Aside from cleaning mild corrosion with a wire brush and NOCO Battery Cleaner, the rest of these signs may indicate a bad battery. Take the battery to your local automotive store and have it inspected by a professional.

It is recommended to keep the battery above 75% (at least 12.4V for a 12V battery) for overall health and longevity. If the battery is below 75%, it is likely beginning to sulfate. Sulfation is a natural byproduct of a battery producing energy.

If your battery has started to sulfate, use the Repair Mode on a NOCO GENIUS5 Charger, NOCO GX Charger, or any model above to help desulfate the battery. If the voltmeter reads 0V, it is likely that a fuse or another connection has been blown and needs to be replaced.

A local automotive shop, such as an authorized NOCO reseller like AutoZone, will be more than capable of load testing your battery. While it’s possible to perform a basic load test at home using a digital voltmeter and a fully charged battery, a professional will be able to diagnose any issues that may come up regarding the battery’s overall health.