For a few days I've noticed the sounds coming from the rear fans have gotten louder. . . annoyingly loud, at times. This evening after a short drive, I parked my car in the garage and plugged it in -- and soon the loud noise began. I took a flashlight and peered behind the left rear wheel, and saw the fan there running. Then I peered behind the right rear wheel and saw the fan there NOT running. Hmm. Shouldn't they both be going at the same time? Is the one making a lot of noise because it's running at maximum and trying to do the job of both?