Sometimes simple things cause the most frustration.
Bought 2001 C5 Coupe that had left low beam facing somewhat down, and right low beam facing up to right. Figured bulbs weren't seated correctly when replaced. Simple fix, right? WRONG. Driver's side I could reseat and it seems fine. Could NOT re-install the right bulb. It simply will not 'catch.' Possible damaged seat on the right low beam housing? (the bulb & fitting seem fine, no gouges, malformations, etc)
Looking for next steps. Is taking off the headlight cover for better inspection and repair a good approach? I've never encountered a bad socket before, but not sure that's the problem. Lot's of parts in the headlight assembly, don't want to do something stupid or unnecessary.

If I can be flummoxed by a lightbulb, imagine what other trouble I can get into.

Papasan

 

Are you absolutely sure it is the correct bulb. Some go in easily and some take much longer then they should. Take a break and try again. Go in thru the surround...you may want to take off the hood adjustor bolt....which gives you a little more room to work.

 

The headlight door and shroud are very easy to take off. Raise it manually with the ****, remove the three philips screws on the shroud, remove the four torx bolts (you'll have to lower it again to remove the two rear bolts), then when you lower the headlight you'll be able to see directly downwards into the back sides of the headlight housings.

The notches inside the housing for the headlight tabs need to be complete free of debris. Also make sure you are compressing the gasket enough so the tabs will slip in. It doesn't need to be hulk forced, but you should be applying some force to get it in.

 

Thanks for the reply and tips (you got past my stupid header). The bulb is a 9006 (low beam) and I did take out the hood adjuster bolt. The bulb was not seated properly by previous "mechanic", and also has a housing surround screw missing (sloppy). Have tried in three different sessions to get bulb to seat in socket without luck (got the three other bulbs to seat rather easily). I also applied silicon lubricant to make installation easier.

Plan B, etc)
*Buy a new 9006 bulb assuming I haven't noticed an existing problem with its tabs (the bulb does light)
*Take off headlamp cover for better inspection view and access to perhaps fix socket
*Replace headlight module/lens if socket is bunged up Would like to avoid this if possible as there are a lot of connections/adjustment fittings to the lens module, not to mention cost and my innate ability to further screw things up. Or am I overthinking it?

Thanks for your assistance!

 

Thanks for the tips on headlight door and compression tip. Now to take off cover for better look & access.

 

The c5s use a 9006 for low beam, and 9005 for high beam. The outside bulbs on both headlight housings are the low beams 9006. The inside bulbs on each housing are the high beams 9005. Three of the four headlight bulbs Lock in place with a 1/8 clockwise turn, EXCEPT the outside bulb on the passenger side (low beam 9006) uses a 1/8 turn counterclockwise to lock in place. Absolutely crazy but true, which is why so many people find it next to Impossible to lock the outside bulb on passenger side in place. Usually happens by fluke when I think they're trying to take the bulb back out and voila it seems to have locked in place by miracle. Why it is designed like this I can't possibly fathom. One thing to watch for when installing LEDs, nobody seems to talk about the high beam LED, only the low beams. High beam 9005 LEDs have a tendency to get very close and/or make contact to the arm that raises the pop-up headlight. Sometimes the pop up arm scrapes the LED housing or can hit up against the edge of the LED which will crack the mounting bolts for the headlight casing. Happened on my vehicle. My passenger side high beam LED hits the pop up headlight arm whereas my driver side doesn't. Go figure? I've tried the TorchBeam 33,000 lumen T8 which worked great until one day the lights motorizing down cracked the housing due to impact with the pop-up arm. Now I'm trying a Sealight 33,000 lumen modified by grinding one of the three prongs smaller and inserting bulb with socket connection on top. Barely can get plug connected, but gives me just enough room to clear the pop-up arm.