What is code E90 on Zanussi fjs1225w?

I have started getting code E90 on my Zanussi fjs1225w. All lights go out and the machines refuses to do anything until I spend about a minute pressing every button to get it going again. The code is intermittant sometimes it appears up to 4 times sometimes not at all in a cycle. I have checked all pipes and filters and all seem clear.

The instruction books do not list code E90, and if the part is going to be expensive ie circuit board would I be better getting another machine.