The light on my passenger side sometimes wont turn on if i turn my lights on and off a couple of times it will then turn on but there is about a 50% chance it turns on. Is this the ballast or the bulb. And also now it wont turn on at all. So should i just buy a new bulb and ballast or just a ballast? I know it is a 55w Ballast but how do i find the right replacement or will any 55w ballast work.