siemens lady 45 model sr73220gb/10 not heating water?

Hi,

Found our dishwasher full of water the other day and managed to work out that the water is not heating up within it. I've check the element and the temp sensor, but they both test as fine. Any other ideas as to what it could be? I'm wondering about the mechanical timer but not sure how to test this.

Just to make the issue more complicated, whilst I was taking the machine apart a metal plate fell out and I don't know where it goes back to. It's kind of rectangular with a sliding piece on it and has three prongs - although I can't see where these go. Any idea where this sits in the machine?

Thanks in advance for any comments,

Brad