So I got a cheap Light Switch, made in China of course, for the Audi A4. It didn't work although they claim it should (I believe is made for the B7 instead of the B6). By the way, the symptom is that the car will leave position lights on even when the switch is off.
As my real problem was the plastic fade off on the switch (it works fine), I decided to swap them so here is a little write up.
Here are some pictures of the process:
Old vs. New
Old switch, to get the plastic part out of it, you need to move the switch to the left a little after prying the plastic tabs out, once you take it out it has a raised part, that has to come out of only one place. Once you see it, it makes perfect sense as always...
This whole thing is a piece, careful with the little springs, they shouldn't get out.
To get the switch plastic out you need to pry out the connector and electronics, you can use a little flat screwdriver
These are the new switch parts
And this is the final result, looking new, old electronics for around $30.
