E41 - Water level detect sequence incorrect?

i have an ancient Hotpoint microprofile 1400 wd 9945 that keeps showing the message "E41 - Water level detect sequence incorrect. " when i switch it on. It starts to fill then bleeps, and annoys the hell outta me!!!
I guess i just wanna know, A) what the F@@@ that means and B) what can i do about it????
Any help appreciated as I'm on my own and skint lol :-D
Thanks