It seems that CarreraCup03 from the rennlist forum has done this retrofit. On post #36 he posted:

"OK everyone ... here is what happened. I plugged in my new ECS auto headlight switch, and everything worked. I made no mods with durametric. I replaced the non auto switch with the auto switch ... took maybe 10 seconds. I then switched to auto ... car was in the garage, and the lights went on. I then pulled out of the garage and the lights turned off (sunny day). I did this 5 more times to confirm and it all works perfectly. Wow what a great upgrade with no other mods, other than the correct switch. All functions on the switch work as well. Auto lights are a great feature."

His car was a 2005 CTT.

Here is the link if you guys want to go thru the details

http://rennlist.com/forums/porsche-cayenne-forum/489859-auto-on-headlight-retrofit-06-cayenne-3.html

I might give this a try and see what happens

 

This was one thing I couldn't wrap my head around when I got my .2 Turbo S a month ago. Even my old 2004 Chevy silverado work truck from years back had auto headlights

 

I was thinking the same thing when I got my .1 turbo in May when my 2004 M3 has auto headlights...

 

The thread and the fix were Cayenne specific - unfortunately doesn't apply to 997's.

 

This would be a nice option to have for sure.

 

While we're at it, lets get the passenger window to auto roll up

 

Mine does....

 

Mine doesn't!

but is auto down only? whats that about? figured there was just something wrong with my car.

 

I read the manual on this one. It is auto up after the half way point.

 

Yes, this exactly. The driver side is a true auto up, the passenger side is auto up after the half way point. I'm sure we'd all prefer the passenger window to function like the driver window.

Auto headlights would be great too.

 

I thought about this thread a little more, and I realized that the auto up function for my windows might be one of the features of the Smart Top module that I installed. I installed that unit right after I bought the car, so I don't remember how it functioned before.

 

Another alternative to automatic headlights if you have a 997.1 turbo with Sport Chrono is to activate the DRL option in the PCM individual settings. This option turns the lights on all the time, so it's not exactly automatic, but it does turn them off when you turn off the ignition. I'm not sure if this is possible in 997.2 cars with PCM 3.0, or with the 2009 cars with PCM 3.0.

 

convertible passenger windows are auto up at any point. Not so with the coupes, which is just asinine.

 

They do that already.

 

I have an Australian Cayman 987.2. I am not sure how my light switch compares to the 987.1 and 997.1 series. About 3 years ago I purchased a universal headlight light sensor kit. I used this to apply a negative voltage to one of the pins on the back of my headlight switch. There are pins for each type of light, i.e. fogs, parking lights, headlights etc. This turned on the headlights when there was darkness. The dashboard lit up except the PCM and ventilation controls. I then placed a diode (1N4002) from the headlight pin (5?) to the parking light pin (2?). Everything then worked as it should.
Prior to this I tried a VW Golf switch with auto function. It plugged straight in but its internal electronics work in an entirely different fashion and this was unsuccessful.
Interestingly, our cars already have the hardware in place. There is a light sensor in the centre of the dashboard that allows the Coming Home lights to work only in the dark. I think that correct programming would enable automatic headlight function but it is probably impossible to 'crack' the system.