I did it last weekend, here are the instructions including pictures:
http://porsche996turboblog.blogspot.com/2012/04/solisto-iphone-mp3-interior.html
Solisto iPhone MP3 Interior Installation
Two years back or so I did a very easy installation of the Solisto device in exchange for the CD Changer in the trunk. Plug and Play. The downside is you cannot attach another device while driving or reboot it when it crashes.
The TomTom Navigation in conjunction with Spotify (or normal MP3 on the device) works really great. Music is turned down automatically when the TomTom lady has to say something, even on/off of the Radio pauses Spotify. Long story short I had to install the Solisto directly at the PCM unit.
1. The toughest part is to get the cover around the PCM off. It is attached with a few hooks. Without tools I read in many forums to push down and pull forward. Depending on the car this might work. I think in my case the cover has never been off so with simple push and pulling it didn't work. To get more grip onto the top part I applied painter tape (to not damage the leather) and on top of it double sided tape. With all fingers on the tape I could pull the cover back, get a grip underneath and carefully pull the cover away.
Tip: apply painter tape to the whole cover so that you don't get any scratches in follow-on work.
These are the hinges you need special tools for to pull them down and get the over out.
2. The rest is relatively easy. On each side of the PCM unit there is a spring. Push them inside and pull the PCM control unit out. There are no screws or anything, just the two springs in the middle of each side. Cover the car's sensitive areas with a blanket or so to not make any scratches.
3. The plug to look for is 'C' on the diagram. It is made up by three parts: yellow, green and blue. Remove it and take apart the plug. Remove the yellow part and apply it to the Solistor connector. Put it back in and re-attach the PCM unit. There is much space to run the solistor cable down behind the PCM CD Nav unit/ AC Unit. I decided to attach the Solisto with Velcro to the carpet between the cardan shaft and the air vents. There is also space behind the AC control unit. The iPhone cable went up to the telephone console. Done!
Reference: Porsche PCM1 Pinout
Borrowed from: Link Forum http://cuoresportivo.no
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Headunit
Naviunit
Disclaimer: THE PIN OUT CAN BE INCORRECT, USE AT YOUR OWN RISK.
All information is provided in good faith. Any modification you carry out, you do so at your own risk. No liability is implied or will be accepted. Please ensure that you are qualified to carry out any work detailed on this page and that you take all necessary precautions.
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Plug A
1 - Speed signal
2 - Free
3 - Free
4 - Terminal 30
5 - Terminal 30 for windscreen antenna
6 - Free
7 - Free
8 - Terminal 31
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Plug B
1 - Loudspeaker, rear right +
2 - Loudspeaker, rear right -
3 - Loudspeaker, front right +
4 - Loudspeaker, front right -
5 - Loudspeaker, front left +
6 - Loudspeaker, front left -
7 - Loudspeaker, rear left +
8 - Loudspeaker, rear left -
Note Plug B is assigned only if no amplifier is installed.
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Plug C
1 - Lineout, rear left
2 - Line out, rear right
3 - AF ground
4 - Line out, front left
5 - Line out, front right
6 - Terminal 30 for amplifier
7 - Control lead for CD changer
8 - Terminal 30 for CD changer
9 - Free
10 - Data lead
11 - Clock lead
12 - Reset lead
13 - Free
14 - Free
15 - Free
16 - Free
17 - Free
18 - CD AF, ground
19 - CD AF, left
20 - CD AF. right
Note Plug C consists of 3 parts.
Pins 1 to 6: yellow housing.
Pins 7 to 2: green housing.
Pins 13 to 20 : blue housing.
Pins 1 to 6 are the loudspeaker outputs to the amplifier. They are assigned only if an amplifier is installed.
Pins 7 to 12 are the control leads for the CD changer.
Pins 18 to 20 are the loudspeaker outputs of the CD changer.
Pins 7 to 20 are assigned only if a CD changer is installed.
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D-Antenna lead
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E-Fuse
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Plug I
1 - Video signal, red
2 - Video signal, green
3 - Free
4 - Free
5 - Free
6 - Terminal 31
7 - Free
8 - Free
9 - Free
10 - Terminal 30 for navigation
11 - Terminal 58 d
12 - Free
13 - Terminal 30
14 - Video signal, blue
15 - Video signal synchronisation
16 - Video signal ground
17 - Free
18 - Free
19 - Terminal31
20 - To combination plug IIIpin 6
21 - From combination plug IIIpin 11
22 - Free
23 - Fuel consumption signal
24 - Speed signal
25 - Free
26 - Terminal 30
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Plug II
1 - Diagnosis lead
2 - Terminal 15
3 - Terminal 86 s
4 - Data lead to navigation unit
5 - Free
6 - DSP (amplifier) ground
7 - Handsfree microphone ground
8 - Handset microphone
9 - Handset speaker
10 - Terminal 30, handset
11 - Free
12 - Voice output ground
13 - Voice output
14 - DSP (amplifier)
15 - Data lead from the heater / AlC unit
16 - Free
17 - Data lead from the navigation unit
18 - Free
19 - Free
20 - Handsfree microphone
21 - Handset ground
22 - Handset on-hook contact
23 - Free
24 - Free
25 - Free
26 - Free