Ok, I admit, haven't consulted the manual for this one. But, on my car on the windscreen wiper arm, it's got written 'PULL MIST'. I assume, that if you pull the arm towards you, water squirts out and the wipers go.
With mine, if I pull that lever, the windscreen wipers just go. Then, on the button to the left, water comes out and the windscreen wipers go.
I'm guessing this isn't the way it's supposed to be?

