Brake Sensor problems of the 2007 BMW X5

Vehicle experiences dsc and awd and 4x4 malfunction while driving. When the error occurs with gas pedal depressed, car will hesitate by going into neutral and jumping back into drive accompanied by engine revving up to above 3000 rpm. When the error occurs and the gas is not depressed, car will go into neutral and coast, until I engage the transmission. If the car is traveling less than 5 mph and the error occurs, then the car jerks to a halt and the transmission is switched into park automatically. This typically happened in stop and go traffic. Had dealer diagnose the problem, presumed it was due to steering angle sensor needing to be reinitialized, but the error still occurred. Often times, when I start my car and the error occurs prior to be even selecting a gear.