klouisdrk

Just replaced headlights on 2007 A8Q. All lights worked except for drivers side headlight. Disconnected battery before removing headlights. All went well until I turned the lights back on. I replaced both headlights, daytime running lights, and the turn assist halogen bulbs. The one bulb I didn't touch was the tiny 168 bulb the comes on with the headlight. Now the problem is these don't light when in fact they did before. They are causing a fault code and VCDS doesn't remove it. Any ideas on what may be the problem? Really don't want to take bumper down again unless I have to.

jlbell

What are the codes?

klouisdrk

I did not save the print out. The bulb out indicator is lit on the instrument cluster and neither bulb lights up.

jlbell

In this instance, we need to see the codes to help you.

Tstealth32

Is this bulb lit during the day time? The larger bulb is your DRL, the smaller one next to it is a parking light (168). The projector on the right are your low and high beam. This is how mine is set up on a 2008 A8 Base. Other years, country, and rest of world setups may be different.

Also, if any of these lights are aftermarket LED, you will most likely have a bulb out indication unless you've done extensive trial and error or added resistors.

Also, if you start the car at night in a dark garage, and start driving while it's dark, do you still get the bulb out warning?

klouisdrk

Thank you for responding. The 1156 bulb your photo shows does light during the day. The little one next to it the 168 is supposed to light with the headlights at night but does not. They worked before I changed all the other bulbs (did not touch the 168's) now they don't. Every other light works fine. Do you know of anything in VCDS that points to them or a specific fuse that points to them?

klouisdrk

I will rescan on Sat. Do you want to see the entire printout or a particular section?

klouisdrk

I forgot about this post, but I'm getting back in case this can help someone else. The situation with the 168 bulbs not working was resolved by replacing both bulbs. My best guest as to what the problem was is this. After replacing every other bulb in the headlight assembly except the 168's which were fine when I started. They possibly blew out from a surge when I reconnected the battery. Don't know if that's the the answer, Just my best guess