Newbie Please HELP! Whistling sound when car is off

[ECali]

Howdy everyone!
If you have any suggestions, it would be greatly appreciated!
I got home from work tonight and turned off my 2004 Mini Cooper S and there was a loud whistling noise. It is similar to the sound that the car makes when you put it in reverse, but the car was off. I thought that if I let it cool down for a while that it would stop, but I came back 20 mins later and it was still making the noise.

Any ideas of what this could be? Thanks everyone!!
Happy Holidays!!

[bad venge]

Check the fans , might be stuck on , bad relay or thermostat switch

[ECali]

I ended up taking my car into the shop and the power steering pump went out. So, $1100 later, it's all fixed. Thank you for your response and help!!!