ye don't do it if you don't want the car soaked, just ask Mini williams mum and dad, on the last run they were sitting next to me in Asda's car park and by accident i operated them oops. I thought to be honest you had to have you main lights on not just the side ones for them to operate, must check when i get home.
THey work with sidelights or headlamps on.
They will operate on the first use of the windscreen scoosher and then normally every 3rd application of the windscreen scooshers