We had this model in our previous 1993 MH - I recognised it by looking up YouTubes. One has plenty of positive comments, might be worth a look: https://www.youtube.com/watch?v=c7C3sMHu0Qs
But there are others that I haven’t looked at.
I hope you can repair it, because a replacement cassette might be less easy to find & it might not solve the problem.
Let us know how you get on.
thank you i have viewed all the videos on YouTube
ive replaced the pump and fuse ,think the whole systemneeds to come out as i think its an electrical fault
Ok. The link I gave you had comments from people who had also changed the pump without success, like you, and they got sorted by following that video.
Anyway, let us know how you sort it yourself because it might help others looking for help.