2008 HID Replacement: Failed again after 2 weeks :-(

Hi All,

My Driver's side headlight recently started 'switching itself off' - which I understand is a pretty common problem.

I'd already had the Passenger side replace a couple of years ago - by the dealership.
But this time I figured I'd do it myself.

So I bought, and installed 2 of these:

The light quality is good, they seem brighter than stock. And whiter too - without being 'blue-white'

(I installed these Yellow Fog Light bulbs at the same time, and they look good.

)

I was VERY careful not to touch the glass of any of the bulb; I wore new surgical gloves and also didn't touch the glass at all.

BUT ... my Driver's side Headlight it acting up again!
Intermittently blinking out.
After only 2 weeks!

So I am wondering: What should be my next step?

• Should I assume it was a bad bulb, or that I accidentally touched the glass, and replace it again?
  
• Or is there something else in the headlight system that I should check/replace?

Many thanks!

 

Many thanks for the info Eric.

• Is there any way to test the ballast before replacing it?
  
  
• Or is it possible to swap the ballast between the Driver's and Passenger's sides - to see if the problem moves?

I'm sort or wary of spending $300, because I am planing to trade it in in early 2015 (for a newer Prius )