Is it moving at all when you activate it or is it totally stuck ?
I forgot to move it from the "locked" position below the lights the
last time I had my V40 washed - When I started the wiper it wouldn't
wipe of course.... Realising what I had done I "unlocked" it and now
it was stock halfway across. - Tried the wiper a few times - Still
stuck.
I gently forced it back to the locked position but gave up as I
wouldn't make more damage than I had already done.. But just as I was
about to go to the dealer and get it fixed I checked it one last time
and bingo - It was back in the normal position... Don't know how!
( Not much help though but......)