Ah, well you cant tell, had a problem with my car when it was 12 months old, no grip in the snow, took it back to Audi could not find any thing wrong. 5 months later when I came back from my holidays car would not start, flat battery. Took the car into Audi, fault was a low voltage from the alternator, this caused the ECU to switch off traction control, and ESP. New alternator problem fixed. If you have cruse control fitted set the speed slightly to fast for a corner, if its working it will apply the brakes and knock you out of cruse control.