It sounds like its your battery that is bad. To test I usually tell people to do the follwoing. Fully chrage the battery, then take it for a spin. If you notice sudden drops in your battery indicator then you know the battery has a dead cell and needs to be replaced. If the battery doesn’t charge then it could be the fuse near the charging port that is blown, therefore the batteries aren’t receiving the charge. Last but not least, your charger could be bad, to check that you would need a multi meter to measuer the DC voltage with the charger on (you should get about 26 – 29 volts).