How long does the fan run for? Is it timed or is it based on your engine temp?

This is the first car I've had where the fan spins after I turned off the car so its new to me.....

 

The cooling fan(s) and or water pump will run for a certain amount of time after engine cut off. I think its determined by engine temp, when it reaches a certain point it cuts them off.

 

This is basically BMW's version of a turbo timer. If you've ever had one of those, they basically keep the car running for a short period of time after you take the key out to allow the turbo to gracefully cool down.

 

Four of my last 5 cars have had an electric fan that at times would run after power off.

1988 Nissan Pathfinder
1992 Nissan Maxima
1997 Toyota
2003 BMW 525 IT Wagon

the only one that has not is the 199 Dodge 1500 Pickup.

Many cars now have these in them.