I have a 2008 GTC with a dysfunctional driver's side low beam headlight. I changed the bulb, popped in a new D2S HID xenon... seems to be correct, but the darn thing still doesn't function. What else could be the problem? I checked the facia fuseboard #12 and it seems fine. The neighboring high beam works. eh?... silly thing. Maybe it will be alright in the morning, but I suspect not.

Oh, and FWIW: I discovered there's a slot in the sheet metal behind the headlight housing... one must remove the inner fender/wheel well plastic to access the slot... but that slot is very handy to fish the headlight bulb out of the headlight housing if one drops the bulb inside the housing when attempting to replace it... and that slot is just darn handy as well for actually changing the bulb.

 

If you have a good bulb and good wiring, then another component is the ballast. There is a ballast for each side. These do burn out too. Check that next.

 

Thank you! I rather figured that's what was up, but I thought I'd ask before I pull the bumper skin off (again)… as I presume the ballast is inside the headlight housing/assembly, thus requiring removing the housing to change the ballast. I have a replacement ballast ordered and coming. I'll fix the seemingly burnt-out amber parking light in that headlight assembly too while I have it out. I'll report back when I seemingly have made progress in the correct direction.

 

Update and question: I've purchased a replacement ballast and have unbolted the headlight housing, but cannot figure out how to remove the headlight housing from the vehicle. Does the fender have to be removed to remove the headlight housing? I presume the ballast is accessed via the square cover plate on the bottom of the headlight housing, and if-so, it looks like I might be able to remove that cover plate and R&R the ballast without removing the headlight housing entirely... maybe be able to get to the back two torx head screws for the cover plate with a long torx screwdriver, going up from underneath/behind the inner-cooler... maybe? Or can the body colored (blue in my GTC's case) painted metal panel below the headlight and which includes the top bracket of the inner cooler and wraps around to where the top of the side of the bumper skin attaches, can that metal panel be removed in a civilized manner?

Any advice from those who've been there, done this?

 

This might be the same on your 08.

 

I've watched that video, and yes, I believe the '05 GT of Alpine's video is same-same for an '08 GTC concerning the headlight housing... but a big difference I see in the video vs. the current reality of my headlight ballast R&R project is the '05 GT in the video has the fender removed. In the video "Luke" points-out the fender is removed, but stated "the procedure is pretty much the same with or without the fender", which in my recent experience, doesn't seem to be the case... near as I can tell... unless the "pretty much" aspect is a caveat... being "removal of the fender".

Also, concerning possibly pursuing R&R of the ballast in-frame (without fully removing the headlight housing from the vehicle): I'm going after the low beam ballast, and based on the replacement ballast I have, I presume there's two ballasts per housing, one for the low-beam and another for the high-beam, as the replacement ballast I have is equipped with a single lead for the bulb connection... and if so, and if I'm successful in removing the ballast access cover with the headlight housing in-frame, I'm wondering if that might prove to be an exercise in futility in dealing with the likely two ballasts within the housing. But I don't know (yet). Previously, in replacing the low beam bulb, out of necessity when I dropped the bulb retainer inside the headlight housing, I discovered an access slot in the metal panel between the plastic inner fender and the back of the headlight housing, which the access slot seems to be intentionally made and located to facilitate access to the bulb sockets. Similar it seems, there's a couple of slots in the metal panel directly below the back two screws for the ballast cover... which I'm thinking may be intentional for accessing those back two screws?