I have had the same problem twice in 48 hours. Not long after starting (in cold weather), the Check Engine, ABS, and ACC warning lights all came on, with the ACC warning also at the bottom of the MID. The car went into what I understand is called "protect" mode, with very little acceleration. On the first occasion, I called out the roadside assistance I have as part of my fully comp insurance, and they took me to the supplying dealer. Who ran the OBD, reset the warnings, took the car for a spin and said "Bring it back if you have any problems". In other words, FIIK. Well, the next day it happened again. Rather to my surprise I was able to limp home (about 20 miles), and tomorrow I shall be taking it back to the dealer. Other than the obvious that this is something to do with the radar or the braking system, has anyone got any ideas? I am not awfully confident that the guys at the dealership know their A*** from their Elbow.