Hi there
I also have this problem, and the warning comes on in the most arbitrary of situations. Nothing wrong with tyre inflation, and there is obviously no spare wheel fitted.
I'm guessing it might have to do with some kind of electronics communication system between the engine and what appears on the dash? The other day I received an error that my engine had a major fault and that a repair was needed. The car stopped working, and wouldn't turn back on initially. I waited another 45 seconds or so though, and suddenly the car started working and the error disappeared after driving for a kilometre or so. It makes no sense!
The most common error, however, is the spare wheel fitted nonsense, and it's the worst on a long journey because it disables my cruise control. Hopefully it doesn't disable crucial safety features too?
Has anyone managed to resolve this issue?