2/28/15 TWITCH IN STEERING AT 55 MPH. (5 TWITCH/8 MI.) HAD BEEN SNOWY WITH SUBZERO TEMPS, AND SUSPECTED ICE IN STEERING LINKAGE. FOLLOWING DAY EXHIBITED SAME TWITCHES, BUT FEWER. BACKING OUT OF PARKING SPACE WHEN STEERING BECAME VERY DIFFICULT. MESSAGES ON DRIVER INFORMATION: POWER STEERING FAILURE, ESC REQUIRES SERVICE, AND A YELLOW TRIANGLE WITH WAVY MARKS WAS ILLUMINATED. DROVE 2.25 MI TO RELATIVE'S HOME. TURNED CAR OFF & RESTARTED; POWER STEERING WORKED AGAIN. NEXT DAY CHECKED FUSE CONNECTIONS ON PASSENGER SIDE OF CONSOLE, AND UNDER HOOD NEAR BATTERY. 80A POWER STEERING FUSE WAS LOOSE ON ONE SIDE. NUTS SECURELY TIGHTENED, BUT RIVETS ON FUSE BODY WERE LOOSE; LUG COULD BE MOVED APPROX 1/32". REPLACED FUSE, AND WORKED BETTER. THEN NOTICED THAT TWITCHING HAD RETURNED; WAS PREVALENT WITH VEHICLE STOPPED AND RUNNING. ON WED DROVE VEHICLE TO PICKUP LUNCH,; STEERING WHEEL WAS TWITCHING WITH CAR IN PARK AND ENGINE RUNNING. USED REMOTE START SYSTEM TO LET ENGINE RUN AS IT WAS NEAR 0 F AND HAD ONLY DRIVEN 3 MI. RETURNED TO CAR WITHIN 10 MIN REMOTE START RUN TIME, INSERTED KEY; POWER STEERING DIDN'T WORK & SAME MESSAGES DISPLAYED. STOPPED & RESTARTED CAR; POWER STEERING DIDN'T WORK. ARRANGED FOR REPAIR, AND DROVE CAR TO SHOP LATER THAT AFTERNOON; POWER STEERING WORKED, BUT LOTS OF TWITCHING. STEERING COLUMN REPLACED DUE TO STEERING WHEEL TORQUE SENSOR CODE C0545. POWER STEERING FAILED AND FOUGHT ME AS EVIDENCED BY UNEVEN JERKY TURNING FORCE. SYSTEM A