First of all try testing the battery with an electrical multimeter tester or any tester and make sure that the battery has a current if it does it rules out both the charger and the battery as the problem then it means that the bulb is probably bad try replacing it and it should work if there is no current running through battery then this means that the battery is bad or the battery and charger are not compatable but if it all came together this should not be a problem
Answers & Comments
First of all try testing the battery with an electrical multimeter tester or any tester and make sure that the battery has a current if it does it rules out both the charger and the battery as the problem then it means that the bulb is probably bad try replacing it and it should work if there is no current running through battery then this means that the battery is bad or the battery and charger are not compatable but if it all came together this should not be a problem