I've read every post I can find here regarding headlight issues in 955's, and I still cant figure out what's going on with mine.
I have an '06 S with Xenon lights. Recently got the "check dipped beam" message, and my drivers side headlight started flickering. So, I pulled it out, inspected the wiring harness, and determined that it needed to be replaced (did the passenger side last year).
I ordered and installed it, and now the beam doesn't adjust when I start it. It appears to be stuck in place and the drivers side beam is slightly higher than the passenger side. I reinstalled the old harness, and it didn't adjust with it either.
Could the control unit be going out?

Any suggestions would be appreciated.

 

The only time I got the "Checked Dipped Beam" message was when the connector was not seated correctly into the headlight assembly. But even then the headlights adjusted when I turned them on, so you might have more going on.
Did you open the headlight assembly and check to see if the internal wiring has cracked/missing insulation?

 

No, I haven't opened up the back side yet. Guess I can do that and take a look tonight.
No more check dipped beam, since I replaced the wiring harness.
The headlight beam not adjusting, and being to high is my only issue now.

 

In a 997 with Xenon lights, you can force a beam adjustment by turning the headlight switch in with the car off, then insert the key into the ignition, turn it to the accessory position so the lights come on but the engine doesn't start, and wait 10 seconds or so. The lights drop down then self-adjust.

Might be worth a shot in the Cayenne.

 

I saw a previous post and tried to force an adjustment, but no movement on the drivers side one.

Any more suggestions?

 

Mine would not dip for a while. I found the problem was the connector at the back wasn't seating fully. Try removing either the engine trim on that side or the front wheel arch in that side. Then try to more full seat the connector.