I have a 2010 IS250 C and having some headlight troubles. The headlight on the driver side looks a little more yellow than the one on the passenger side and out of the blue it just turns off. If I turn the headlights off and then turn them back on it will usually always come back on. Is this problem normally the bulb or could it be a ballast.

 

Also I gave the VIN to my dealer and he says it does have the HID bulbs

 

Swap the bulbs between left and right and see what happens. I think you have a problem with the ballast, though

 

Good idea. I'll try that. If it is a ballast are they trouble to replace?

 

Youll have to take off the bumper and headlights to access them

 

Good point. That's a difficult job just to try and see. Is it easier to swap the ballast? I'm think no; that it requires the same thing.

To the OP, if you have to take the bumper off to test out the swap(s), I'd be sure and have a new bulb, possibly two, and a ballast at the ready because you sure don't want to have to put the bumper back on while you're waiting on a new bulb or ballast order to come in.and to the bumper removal and replace over again.

Also, while you're at it, any LED upgrades on the turn signals should be ready if you desire that. I would do this myself, but can't bring myself to do the whole bumper off/on thing.

 

Lots of misinformation in this thread.

First, having the bulb come on and then randomly go out could be the ballast, but more often than not it's just the bulb. The advice given by DennisMik is correct, swap the bulbs to determine whether it's the bulb or the ballast.

You absolutely do not need to remove the bumper to swap or replace the bulbs. You only need to remove the windshield wash fluid fill tube to access the driver side, and you just need to loosen and move the air box to access the passenger side.

 

I found a site on YouTube that showed how to replace the bulbs without removing the bumper. This weekend I will try swapping bulbs

 

Easy way to determine where the problem is. Thanks for this, never thought about swapping sides on the bulbs.

 

^^ 100% correct.
1) Most likely the bulbs. D4S have no mercury in them and have a limited lifespan compared to D2S.
2) Swap the bulbs. DO NOT touch the glass or it will explode when on. Wipe with methanol or acetone if you touch it.
3) Bumper does not need to come off to swap bulbs. It's all pretty obvious once you put eyes on the cover where the bulb is.

Look at good replacements. OSRAM CBI or CBB is a good start.