[s-cars] Problem with OEM Xenons

[Sean Douglas]

I have the OEM e-code xenons in my S6 and am having a problem. I installed
them myself over a year ago with no issues.

 

Last week, while the car was parked and locked, the left low beams came on
by itself. I played with the switch and it wouldn't turn off, so I pulled
the fuse which interrupts the constant 12V to the relays and it turned off.

 

The relays are mounted inside a sealed control box that I assume houses the
ballast and igniter as well. There is constant 12V running to it, which I
have fused as well as switched power from the headlight switch.

 

I thought the problem might be either a bad headlight switch or even an
ignition switch.

 

When I got home, I put the fuses back in. The next day, I was driving in
traffic and one of the low beams came on by itself again (I could see the
reflection), so I cycled the headlight switch and after a few tries it went
off, but they would not come on again - but finally did only after several
tries.

 

So later, I experimented and pulled both headlight fuses in the fuse box by
the driver's door. I figured if they still came on with these fuses pulled
then I have eliminated the headlight switch (switched 12V) in the circuit
and it must be the control boxes.

 

This morning I went out to my car and the *right* headlight was on, so now
I'm thinking both left and right control boxes are bad. Somehow 12V is
getting to the headlight and I'm suspecting it's the relay inside the
control boxes.

 

I know OEM xenons are rare and few listers have them, but has anyone tried
to take apart the control boxes? The downside is that the control box and
bulb are hardwired to each other and sold as one piece which is very
expensive. Last time I checked they were around $400 euros each!

 

Some people have suggested it might be the ignition switch, but I fail to
see how it is leaking 12V to the headlights. I guess I'll try replacing the
ignition switch as it's cheap to see if it fixes the problem.

 

Any electrical gurus out there that can offer advice?

 

Thanks,

 

Sean Douglas

1997 S6