Got in the cayenne today for a drive, the PCM display powered up with the Porsche emblem but then after 20 seconds or so powered off. Tried turning it back on, came on but did the same thing. Radio, nav. ect do not come on. I can load a CD into the unit but it doesn't do anything, it will also eject the CD without any problems. I checked out the radio fuse and it was good. Drove it last night with absolutely no problems???

Any suggestions, is the PCM pooched or do I need to reset something?? If it's pooched what would be my best replacement option?? It is my wife's vehicle so no need to spend allot of money to upgrade. The vehicle came with a bluetooth system and Ipod connection so probably another OEM unit would be the easiest but would buy a used unit over new from the dealer.

All suggestions are appreciated