Answer to: Why are my fans constantly running?I had the same problem on a MacBook Pro 8,2 (2011). After disconnecting all devices, I shutdown and reset the SMC which didn't appear to help all on it's own. After rebooting, the fans started again at 100% and so I put my MacBook Pro to sleep via the top left Apple sleep menu item. Then waited for a minute or two and the fans finally turned off. Then I closed my Macbook Pro, and reopened it, and logged back in and the fans were working properly again. (Note I also tried running smcFanControl before resetting the SMC but it didn't have any effect on the fans).