This is what the error code book says
• E30/31 - A motor drive problem has occurred. Try running the programme again. If the problem persists book a service engineer.
an addition to that is to check the motor brushes to see if they are worn if they are it is a relatively easy & cheap to fix rather than calling an engineer out, if you are unsure what to look for I sure someone you know can help, this is a fairly common problem with all househol motors
Graham
May 2006