Under the filters right at the bottom of the sump you will find the drain pump - you can get to the impeller blades by removing the top cover secured by a single Torx screw.
You may well find bits of broken glass - lemon pips - bottle foil jambing up the blades - tweezers will help.
The blades should rotate easily with a bit of magnetic resistance.
The body of the pump will be in the same place but you get to it from below.
I am not an appliance engineer.
Good Luck..., February 2016
