Hey Enrico,
We have found the problem when you put your steering wheel on make sure it is perfectly straight and the hicas sensor is in the right place.
what happens is when you have been driving for over 20 minutes the computer senses that you cannot be turning all that time and has a dummy spit the arse end kicks out and light comes on.
I had been to many mechanics here in sydney and none of them
knew what they were doing some supposed import specialists.....
Try this and let me know how you go.
Regards,
Daniel