mkongsiri

I finally decided to breakdown and tackle the annoying adaptive headlight failure warning every time I started the car. I don't recall which error it was on the VCDS, I think it was short to leveling motor. As many have shown before, you can only access the vertical motor from the rear access panel. These are simple stepper motors, I know these kind of motors rarely fail and it's more likely a wiring failure. But how do you access it as the enclosure is sealed? Simple, with this:



Then you do this:


Once you get it open, you can remove the torx bolts that hold the front inner cover and remove the entire bulb assembly.

Upon inspection, it was as I had expected. The insulation on the wiring was crumbling away due to the heat of the bulbs and shorting out the circuits. Here's an example of the headlight position sensor wiring after handling it, the insulation just crumbled away:



[IMG]<a href="http://www.freeimagehosting.net/"><img src="https://i.imgur.com/IdDMLMs.jpg" alt="Free Image Hosting"></a>[/IMG]

[IMG]<a href="http://www.freeimagehosting.net/"><img src="https://i.imgur.com/DQDhqAa.jpg" alt="Free Image Hosting"></a>[/IMG]

(I had more pictures of the repair but my phone took a crap so I lost most of them, sorry!)

There was no way to try to repair the existing wire (and no point) so I ended up replacing EVERY wire in the entire headlight assembly with new wires soldered in. It was a long arduous process that took about 3 hours, but it got done.

Re-installed everything and used my soldering iron tip to reweld the plastic housing back together. I also put a bead of RTV on the seam just in case. Viola, adaptive headlight error fixed. Again, I don't see the motors a likely failure point, it's the heat from the headlight bulbs cooking the wiring. I also put aluminum foil around the wiring harness to act as a reflective heat barrier.

Replace the headlight for $1500 from the dealer? $500 from ebay? Yea I don't think so. I'm putting my money into my boat instead.

Pentium3210

Ouch, it's good to see you fixed the problem, but I need extra caution or an emergency Headlight in case of anything goes wrong!

^_^

Pentium3210

do u have a video "How to close the headlight after this"

mkongsiri

There's really no video needed. As I said in the post, use your soldering iron and weld (melt the plastic back together) by running it along the cut seam. This method works very well for repair all kinds of plastics. They even sell plastic welding rods, but it's not necessary for this.

Pentium3210

maybe I don't have the courage to do something like that

I will wait and check maybe I can find some good deal before

Thanks!