I've had a very distressing situation arise with my 1 year old i3 Rex. I was driving to work the other morning in the dark and in the middle of an overtaking manuoevre the DriveTrain error appeared on the screen and the power on the accelerator went completely. The message said to stop driving and switch the car off....very scary message to get when driving especially when overtaking. Fortunately, the road was not busy and I managed to coast along the road into a layby but normally this road is very busy and this completely unexpected failure could have caused a very serious accident. I've had not previous errors alerting me to any problem with the car, engine or battery. The car was charged, I was not using the range extender, I was not on an incline and I was only accelerating from 55mph to 60mph so the car was not under any strain. BMW have said the problem has been fixed, there was a sensor problem and something wrong with the engine. I wasn't using the engine so why would a failure with it affect the acceleration and power. I've lost so much confidence in the car. What if this error had happened on busy motorway at 70mph with my kids in the car. Has anybody else had this problem? Not sure what to do next. I can't be expected to continue to pay for a car I'm scared to go over 55mph and overtake in.