ON JULY 4TH 2018. I WAS DRIVING DOWN FREEWAY AT APPROXIMATELY 74 MILES PER HOUR, MY VEHICLE DECELERATED ABRUPTLY DOWN TO ABOUT 40 MILES PER HOUR THEN DOWN TO 20 MILES PER HOUR. STEERING WHEEL BECOME TIGHT AND PRACTICALLY LOCKED INTO PLACE. THIS PORTION OF THE EVENT OCCURED WITHEN TWO SECONDS AT MOST. THE CHECK ENGINE LIGHT CAME ON AND THE CONSOLE SCREEN ON. THE LEFT SIDE OF ACCELEROMETER DISPLAYED MULTIPLE MESSAGES STATING MY SAFETY SYSTEMS WHERE NOT AVAILABLE, ADAPTIVE CRUISE CONTROL WAS UNAVAILABLE, FORWARD COLLUSION WARNING WAS UNAVAILABLE, REAR PARKING CAM UNAVAILABLE, PARKING SENSORS, UNAVAILABLE, HILL ASSISTANCE UNAVAILABLE, THESE WHERE THE ONES I READ WHILE TRYING TO MAKE AVOID A COLLISION BUT OTHER MESSAGES CONTINUED TO DISPLAY ON THE SCREEN. ALTOGETHER THE EVENT IN WHICH THE DECELERATION AND MESSAGES DISPLAYED ONE AFTER THE OTHER, IN RAPID SUCCESSION, TOOK PLACE INABOUT 5 TO 10 SECONDS. THE SUDDEN DECELERATION OF MY VEHICLE, FROM 74MPH TO 20MPH FORCED A LARGE WHITE SUV. TO QUICKLY ADJUST LANES AND FORCE TWO OTHER VEHICLES TO MOVE AS WELL IN ORDER TO AVOID AN ACCIDENT. ONE VEHICLE WAS ALMOST FORCED INTO A CONCRETE WALL BUT WAS ABLE TO STOP, THE CARS BEHIND HAD STARTED TO MANUVER AROUND AS WELL. I THE DRIVER WAS ABLE TO CORRECT THEMSELVES QUICKLY AND CONTINUE ON. MY VEHICLE WAS UNABLE TO ACCELERATE PAST 20MPH. THE EXIT WAS CLOSE, MY HAZARD LIGHTS APPEARED TO BE BE WORKING, AND VEHICLES WHERE PAYING ATTENTION TO MY VEHICLE. I TOOK THE OPPORTUNITY TO MOVE THE VEHICLE OFF