They are an electric motor for puntos. My guess is that its stopping working on full lock and has just started since the weather has got cold. Its a common fault on the mk2 puntos, and it seems on your mk3 punto. motors and steering columns are between £50 second hand to £100-£250 new. Try the punto forums for how to guides and where is best to buy them. Its not a big job, just involves taking dash off, and swapping parts