56 Megane - offside wiper not moving?

[tigger1]

o/s wiper doesn't want to move with the n/s one. Will move easily if you pull it by hand (n/s one won't) - so I'm guessing something is broken. Is it even worth me getting wet to have a look - or should I forget about taking the car tonight and just nip it to the dealer to get sorted tomorrow (under warranty).

And will it be a quick job for them or will I have to arse about finding my own way to work even though it's a car under warranty (no, I'll not want to pay £15 for a courtesy car, thanks )