Cooling fan keeps running

[dadysev]

Ok, its not running fast but its closed to freezing out now, and this has happened twice over the past few days.
I got out of the vehicle and noticed the front cooling fan kept running at low speed, so I stayed out watching and waiting for a few minutes but no change. I couldn't bother anymore, but I noticed if I start the engine and turn it off again it shuts off.
Is this a sign the fan is going or is this normal?

I have an F10 550i and this happens after hard driving to cool down the turbos, so I know that is normal, but I never noticed it in my old E46 with the same motor as this X5.