internal water pump

where can I find the water pump in a vw topaz, I have no pressure and the water trickles out !! cant locate it !!

The AS Topaz manual says it's located under the floor of the wardrobe. I have not been there but if you compare the inner length of the gas bottle storage compartment with the length of the floor of the wardrobe, you will find that there is a space beyond the end of the gas compartment of about ten inches which is where the pump is hidden. I think you will need to remove the back panel inside the wardrobe prior to lifting the floor panel. Bon voyage !

That's right. You'll need a pozi screwdriver to undo the screws at the back and the carpetted panel lifts out. I'm told these mamifold type pumps are pretty hardy, but I am having intermittant problems with mine too at the moment.
Are you intending to replace yours or are you after the inline filter?

yes, that is where it is, mine works okay but is just soo loud when it works, dread flushing the toilet in the night on a camp site