Kiselo, huge thanks for taking the time to post this after finding the solution. I think this is a pretty common problem, and one that a whole lot of googling is required for before you land here - even though I first came to FiatForum a while back. I've got a manual arriving any day now, but I like the sound of your solution very much, especially the permanent fix bit! It might be a duff contact somewhere inside the Siemens fan, perhaps, as mine often comes on after a bump in the road., but I'm just going to get the Denso if it is available at a reasonable price.
Thanks!
