Ballast or Igniter????
 

My "bulb" went out a little while ago. I was waiting until it got a little warmer to change it. Today was as good as any. Anyway, I replaced the bulb, and no go. So now I'm wondering if it's the ballast on the bottom of the casing or the igniter inside. The reason I'm saying igniter is because as I was taking the assembly out, I noticed the cover was completely loose. I guess I over-tightened the screws last year when I upgraded my bulbs and changed my angel-eyes. In short, which one is more likely to be the problem? I know the more experienced guys have come across this before.

Thanks in advance.

Was there any evidence of water anywhere? The ballast "plugs" in through a water-tight (from the outside) seal located in the bottom of the headlamp housing....but if water managed to get into the housing, would act like a drain (draining into the ballast connection).

Have you checked to make sure you have power going to the ballast, and up to the igniter?

Ah....That I did not check. I didn't see any water in the housing. I guess I was wussing out to get my truck back together because the sun was going down and the temp started dropping. But that does sound possible.