Saw my wife spin out on the highway today in our C4S. It was very icy. Nobody was hurt. I tried to drive it out. The front wheels did nothing. I turned the PSM on and off, did not change anything. When she came home I had her try to pull up the driveway. We have a slight incline with plenty of snow. Front wheels did nothing. The car has Blizzaks. I looked on you tube and saw Carrera 4 convertible hanging off the road with the left front wheel in the air. When he gassed it the left front started to spin. I have tried to find out how the system works. I have not seen anything definitive. I called the dealer, he said if there are not any lights on, that it is working. I am tempted to pull the cladding to see if the prior owner pulled out the drive shaft. Any ideas or info?

 

Normal. Very little torque bias goes to the front. Porsche AWD is not like a Subaru or Audi.