I tried the above, but it did not work for me. I looked around and found a German Forum discussing the same problem and used Google Translate. A very bright guy there point to a large capacitor that had gone faulty - this is 0.22uF at 275 volts rating. I took this out and changed it - got the exact replacement on size and rating at Maplin for £1.29 inclu. VAT. I have a soldering iron so replaced it - please get someone who is used to doing such things on mains equipment because of the serious safety issues. The toaster then worked perfectly. Hope this proves useful to others. I guess Siemens had a bad run of this component.
Laurie in Caversham, July 2011