Computer software failure. Intermittent problem that started with a recent software update. When backing out of a parking space, car will move a few feet then go into park and set the parking brake. Putting car back into reverse allows the car to move about 2 feet then the parking brake re engages. This has repeated more than 6 times in the process of backing out of a parking space. (There was at lease 3′ of clearance to the sides of the vehicle and nothing behind the vehicle.) This is very dangerous when backing out of a diagonal parking space that is along the side of a busy road. I have scheduled Tesla service for the soonest appointment which is 2 weeks from now.