I cant seem to understand how this works......the wiper works fine but i dont get any water from the jet..........any ideas anyone..

The reservoir in the boot is full to the brim so its not lack of water...

thanks

Find the pump that the water bottle is fed from, diconnect the pipe from the output side of the pump, try again. If water comes out it will probably be a blockage in the pipe. Does the pump run ? when you operate the switch. Get somebody to watch while you operate. I would imagine the pump is in the boot somewhere and probably attached to the side of the water bottle. Use a bit of logic and you'll get there