I’ve read about this issue happening to others, and it finally happened to me too – the dreaded “Dipped Headlight” error. After reading all of my favorite Audi forums, I found a host of information, some of it helpful, some of it conflicting, and some if it misguided. But piecing together the consistent recommendations as well as a little educated guessing and fact checking, I’ve figured out a good approach for anyone who gets this problem in their 2002-2008 Audi A4, S4 or RS4 and wants to try to fix it themselves. The steps listed here will probably also work for other Audis as well, although may differ somewhat.
What does “Dipped Headlight” even mean?
Simply put, “Dipped Headlight” is Audi-speak for “there is something wrong with your low beam headlight” and can mean a number of things. This is part of why it is so difficult to troubleshoot and fix on your own, as the error doesn’t give you much information about what the problem is. If you have a VAG-COM cable, or know someone who does, the cable can read your car’s computer and tell you the exact error code which will help tremendously. For some people this error message only comes on intermittently, such as when they’re driving slow, when the car first starts up, or in cold weather – for others, it comes on every time.
What to Check First
There are several things that most commonly cause this error after reading dozens of owners messages on Audizine, Fourtitude, Audiforums and other message boards. I’ve listed them below in the order of how’d I’d recommend checking and testing the problem. The simplest thing to do is to replace the headlight bulbs, followed by your headlight sensor in your front wheel well if you have adaptive/auto-leveling xenon headlights. The bulbs are cheap to replace so it’s a good place to start, and if you have symptoms of a bad sensor you can check the connection and make sure it was bent out of place and fix those problems pretty quickly. The other cheap/easy thing to try at first is recalibrating the headlights using VAG-com, which requires access to a VAG-com cable but is otherwise pretty easy to do. Using a VAG-com cable will also help you pull the exact error code which should also help you narrow it down to an issue with the bulbs, ballasts, sensors or headlight alignment problems. Issues with the ballasts or internal motor of the headlight are much trickier, and sadly you’ll probably need/want to replace the entire headlight assembly. Sorry to be the bearer of bad news, but with any luck you can pickup a new headlight and replace it at far less the cost of having the dealer or an independent shop fix it for you…
Typically the best place to start is new headlight bulbs, as they are often the culprit and one of the cheapest and easiest things to fix – even if new headlight bulbs don’t fix the problem, you’ll eventually need to replace them anyway, so consider it preventative maintenance. If you get the “headlight bulb out” message, see your headlights “flicker” on/off occasionally, or notice that your dipped headlight error only comes on in cold weather or at first start up, it’s likely your headlight bulbs may be on their way out.
Follow this DIY for tips on picking the right bulbs and how to install them: http://nickscarblog.com/diy/replacement-d1s-headlight-bulbs-for-b7-audi-a4s4rs4
The ballasts are also known to occasionally fail, which can cause this issue. Rumor has it some ballasts have been recalled by Audi, in which case you can check with your dealer to see if your car qualifies for the recall, in which case the service and replacement should be free – problem solved!
However, if you’re not covered by recall and your ballasts are indeed bad, this is a huge undertaking. To replace the ballasts you have to remove the headlights (and bumper) from the car, as the ballasts are mounted on the underside of the headlight housing. OEM ballasts cost anywhere from $100-200, at which point you may be better off replacing the entire headlight assembly as you can usually find complete headlights (including ballasts and bulbs) used on eBay for $200-300. This also covers you in case the problem lies elsewhere in the headlight housing, and since you’re going through the trouble of removing your headlights this is probably worth the extra $100 over the cost of a ballast to not have to remove all of these parts more than once. Make sure you have the right part number prior to ordering – the part number can be found on a white sticker on top of your headlights which you can see simply by opening the hood – compare this to the eBay listing to confirm you’re swapping “apples to apples” with the replacement housing:
|View all items...||(Powered by: WP eBay Ads)|
To swap out the headlight housings, follow this DIY: http://www.audizine.com/forum/showthread.php/234131-B7-A4-S4-Clear-Corner-Mod-Removal-of-Bumper
Auto Leveling Sensor
If you recently lowered your car, or hit a really hard bump to your drivers side front or rear wheel, this could be the problem. For cars equipped with auto-levelling sensors, the sensors themselves are located in the wheel wheels near the lower control arms so they can adjust the headlight aiming based on the suspension load. For some people when they lower their car, the sensor is out of range as the suspension has been altered. For others, a hard bump to the front wheel could potentially break the sensor or cause it to become unplugged. To access the sensor, take off your drivers side front wheel and look near the bottom of the suspension. The sensor bridges the lower control arm to the body and looks like this:
If it is damaged or the wires have frayed, you can order a new one here: http://www.ecstuning.com/Audi-B6_S4–V8/Lighting/Headlights/Leveling/ES440960/. If you are lowered, you may just need to bend the upper part of the bracket so the top of the sensor is higher again. Once you have inspected and either repaired or replaced the sensor, you will need to recalibrate it using vag-com. Follow this DIY for instructions on how to do that: http://www.a4mods.com/index.php?page=webcontent/pages/autolevel.html&category=6
Headlight Swivel Module
This is the issue I had after replacing the bulbs and ruling out that issue. It turns out that while I was replacing my DRL bulbs, I must have knocked the main headlight swivel out of place, preventing the headlights from being able to aim correctly. Looking closely at the headlight I could see the projector lens on my driver side was pushed forward and not aligned the same way my passenger side was, so I reached inside the headlight housing (much the same way I did when replacing the bulbs) and pulled the projector lens “back” away from the front of the housing until it clicked back into place. I then recalibrated the headlight adjustment using the DIY on A4mods and cleared the codes and the problem went away: http://www.a4mods.com/index.php?page=webcontent/pages/autolevel.html&category=6
If you run the vag-com on your Xenons and find error code 02769 or 02770, it is likely your projector lenses are out of alignment and you may be able to manually push or pull them back into place. It is also possible the motor inside the headlight has malfunctioned or stopped working altogether, in which case you’ll need to buy an entire new headlight housing – like mentioned earlier, eBay is your best bet for that, and expect to pay about $200-300. But hopefully you may just be like me and have to massage the projector lens back into place and reset the headlight adjustment via VAG-com and the problem will go away
VAG-com adjustments (reset to factory spec)
If you change anything other than the bulb, you may also need to recalibrate your headlights and reset the adjustments to factory. To do this, follow the A4mods.com DIY mentioned earlier. For me, I fixed the projector lens being knocked out of place then recalibrated the headlight adjustments using VAG-com to fix my errors.
The last resort is to pull Fuse #10 if you have adaptive or auto-leveling headlights – this disables the feature entirely, which should also disable the warning light. This isn’t the best way to fix it as your headlights might be out of alignment still, and you lose the adaptive features, but hey – at least it gets rid of that pesky warning light and beeping
Still stumped? Leave a comment, I’ll do my best to help…
Recent posts in DIYs