Left dipped headlight
 

Hey guys
So i had a service at the dealer reecently,and after that i drove my b8 a4 for the first time at night, there was a warning sign came on my dash "left dipped headlight/main beam headlight", and if i restart my car, its gone and after 5 mins or so, it comes back and left front headlight just goes off again, restart the car again, its fine then...again, so i guess the xenon is not broken, any idea would cause this??

Re: Left dipped headlight
 

Hi there,
I've just had exactly the same problem and wondered what yours turned out to be. Both headlights went out and I got a Left/Right warning on the dash. I turned them off and on again, and just the right one came on. Trying again they both came on. This morning I got a Left dip/main warning and only the right one is working, but again turning them off and on they both come on for a while. I suspect the left ballast box is to blame but I'm not 100% sure.

Re: Left dipped headlight
 

When you get a dipped headlight warning it has to do with your balast. The balast in these cars is actually the controller for the entire headlight. I learned this when i got the same warning in my B7 S4. It actually controls the auto-level and (if equipped) the adaptive lighting as well.

Re: Left dipped headlight
 

Thanks Brandon,

As it happens it was actually the headlight bulb itself. I bought a new ballast box, exactly the same problem. To save yourselves the same problem in the future, the easy test is to take both headlights units out (sounds like a nightmare, in fact it only takes a few minutes) and switch the bulbs over (being really careful not to touch/damage the glass). With my car the problem switched to the other side. A new bulb later and everything's as good as new. Not really sure what electronics are in the box on the back of the bulb, but they can obviously go wrong without the bulb itself failing.

Re. taking the headlights out, you can find a guide if you search for 'ampoule a4 b8' on YouTube (I can't post links yet) and it's the first one that comes up.

One thing it doesn't make clear is that the two hidden away bolts at the back don't need to be completely removed, you can just loosen them.

Hope this helps.

Re: Left dipped headlight
 

Hi guys!
I faced the similar issue with my Audi A4 b8 and it was xenon ballast keboda which got failed. I bought replacement part from UK website, got it replaced and all good now. Don’t remember full OEM number but you can visit the website from where I bought it http://xenons4u.co.uk/