Yes the fan is not connected through the ignition switch and will operate without the power on or the motor running. I always make a mental check to make sure I shut it off when parking my trucks to keep from leaving it on and killing the batteries. The fan motor in the one in my M715 is so quite that if there is hardly any background noise you can't hear it running. The one in the M725 is a little louder and less likely to get left on.