Theyre not actually headlight washers, I discovered what they are really.
When you have a c*** tailgating you, they DRENCH the car behind you in lovely white/milky liquid. Nissan kindly put the "tailgater" button just next to the ESP button too.
Have a similar problem - had a look under my bonnet for this white non-return valve but couldn't find it. Is it potentially relocated in the HR engine bay?