WE WERE DRIVING TESLA S NORTHBOUND ON HIGHWAY 101 GOING FROM NOVATO TO PETALUMA, WE WERE ON AUTO STEERING WHEN THE DRIVER (MY SON) SAW THE CAR MERGING STRAIT ON US, HE TRIED TO AVOID THE ACCIDENT AND SWUNG TO THE LEFT, BUT BECAUSE IT WAS ON AUTO STEERING THE STEERING WHEEL WAS BLOCKED/STIFF AND AT FIRST HE WAS NOT ABLE TO MOVE IT. IT TOOK HIM COUPLE OF SECONDS TO REALIZE IT. IN ORDER TO OVERRIDE THE AUTO STEERING HE HAD TO USE FORCE TO SWING LEFT BUT ONES THE AUTO STEERING WAS OVERRIDDEN WE SWUNG TO THE LEFT SUDDENLY ALMOST HITTING THE DIVIDER/WALL BETWEEN HIGHWAY'S BOUNDS, THEN HE SWUNG TO THE RIGHT TO AVOID THE WALL, SO WE FOUND OURSELVES SWINGING THROUGH 2 LANES AND SHOULDER LEFT AND RIGHT, GOOD OTHER CARS SLOWED DOWN WITNESSING THE ACCIDENT SO WE DID NOT HIT ANY OTHER CAR, CANNOT DRIVE THE CAR DUE TO SOME REAR WHEEL DAMAGE. I BELIEVE THAT THE AUTO STEERING WAS MALFUNCTIONING AT THIS POINT BECAUSE IT WAS SUPPOSED TO BE THE SAFEST WAY OF DRIVING AND IT CAUSED US TO BE UNABLE TO ESCAPE THE OTHER CAR MERGING TO US AND EVENTUALLY BE INVOLVED IN THE ACCIDENT. TO AVOID OTHERS FROM SAME PROBLEM OR EVEN WORSE I DEMAND TO PRESERVE THE EVIDENCE AND TAKE MY CAR BACK AND REDO IT SO IT WILL NOT MALFUNCTION AGAIN, ALSO THE INSURANCE REPLACED ONLY THE DAMAGED TIRE, SO NOW WE HAVE 3 OLD TIRES AND ONE HIGHER ONE, I HAVE TO HAVE 4 SAME SIZE TIRES.