MIELE TOPLOADER W149 WASHING MACHINE?

I have a problem with the inner lid which, according to the flashing warning light on the control panel is telling me it isn't closed so the machine won't start.The lid is most definitely closed exactly as described in the instruction book.
I suspect theres a switch or something similar that's activated when closing the lid. Anyone come across this before and can offer a solution before I take further action either taking it apart or calling out an engineer?
Will probably need a good competent reasonably priced engineer in SE London/NW Kent area if anyone knows of one.
Cheers,Brian Read

Thanks - all replies acknowledged.