[duncans]

No, you tap the button on the end if the indicator stalk. This gives you a wipe, and a wiper speed menu will appear on the screen if you want to override the auto wiper speed.

Saying that, the auto wipers can be dreadful. They mostly work OK, but occasionally will randomly turn on when it's dry, or not come on when it's pissing down. It's down to the fact that rather than use a simple infra-red based rain sensor (that the rest of the industry has used for decades) Tesla think they can do just as good a job using the front-facing AutoPilot camera and save a dollar or two on a dedicated sensor.