My blower motor came on unexpectedly while driving in quite warm weather. The switch was in the off position and so were the temp controls. When I turned the car off the blower continued working even with the key out of the car. I left it for several minutes thinking it might have something to do with the high outdoor temps but it would not shut off until I pulled the 30 amp temp controller fuse. Several hours later I re-installed the fuse and the blower started again. Could this be caused by the fan regulator? How could it get power without the keys or ignition on?