Liner Must

How can I fix my washing-1999 ML320 rear window?
My rear window washer does not work however when I push the button to do work – it's as if the pump is operating well, I suppose it must be blocked or obstructed. How can I unlock it and / or delete the plastic liner inside the hatch to get a closer look at the mechanism behind? Can I just pull the plastic liner out of the trap?
You may need to replace the washer nozzle and cap at the base of the wiper arm. It is quite easy and cheap to do though.
