While driving her 2002 mercedes ml 500 at a steady 40 mph in traffic the electronic stability control engaged for no reason locking the brakes and making the vehicle uncontrollable and unresponsive to driver input. the only thing that prevented us from being hit was there was no one behind us, had this of occurred going through an intersection we would have certainly have been hit. our vehicle is at the mercedes dealer now and we are being told it needs a brake switch this will be the third or fourth one changed on the vehicle, it also has a bad yaw sensor the part that the dealer says caused the stability control to malfunction. the yaw sensor that is currently in our vehicle is not the original and has a different part number meaning it has also been changed in the past. i have a serious problem with this whole situation vehicle safety systems should not jeopardize the safety of the operator this is a serious safety defect. i have researched the mercedes owner forums and found numerous occurrences of this exact defect on several models of mercedes vehicles one happened while a gentleman was going at highway speed and mercedes has done nothing to take action. *tr