I had simillar situation on dry road, my impression is that whenever I did not have full control over the engine/suspension/curve the lamp was on and the electronics started to control the car.
It was kind of warning to me - full control in the curve, no metter if the road is wet or dry is essential.
By the way, I just expereinced 2nd general reparation of the engine after just a year. I was loosing the compression, the temeprature went up and the car had to stop. My IS220d is 2007/150k km.
Any expereinces?
