Typically it means check the charging system....start by checking the terminals on the battery for corrosion or anything that looks off (sometimes there is something on the terminals that looks green or like powder all over) also make sure they dont move freely when you check them, if they do clean and tighten them. Look at the battery itself and see if there are plastic covers on top that are removable, if so put on some safety glasses and gloves remove one at a time, check to make sure the water level is up and level, if it is look with a flashlight to check and see if any of the holes with water look cloudy (burnt cell is easily identified by cracked cells under the water or cloudy water in the hole) If its low and clear, add water till if fills level with the rest.
If the light stays on after this have the charging system tested, if you are familiar with basic tools we can guide you on how to check the charging system from alternator.
If the light stays on after this have the charging system tested, if you are familiar with basic tools we can guide you on how to check the charging system from alternator.