Electronic Ballast for Herbie is an essential part of the lighting system without which the light cannot work. The lifetime of the ballast is some 3 years. It is easy to change the ballast, you can find it inside the vertical lamp arm and it is connected with two screws and the wires are connected with quick-locks. You can find a short video on the changing of the ballast here:
In case you have purchased a new light and it will not work, you should also change the ballast.