This happened a couple of days ago, and I am sharing it in case anyone else runs into it. I picked up a relative at the airport, and I was in a covered garage that transmitted noise well. When I started the vehicle ('08 Outlook XR) I noticed a loud and persistent whining noise. It was not affected by engine speed. We headed home, and decided to stop at a restaurant. The noise continued even after the engine was shut off, and it was accompanied by a low washer fluid warning. I looked under the hood and traced the noise to the washer fluid reservoir. I went to a nearby Auto Zone and bought a gallon of washer fluid. I added it, which made the noise more faint, but it was still there. I could see the vehicle from my table in the restaurant, and the noise had become loud enough by then for people passing by to notice it. My short term plan was to pull the fuse for the washer/wiper circuit when I got home until I figured out what to do. I noticed when I got in the vehicle that the rear window was wet (it shouldn't have been), and I was getting a low washer fluid warning again, probably 30 minutes after adding a gallon of fluid and parking the vehicle. On the way home I toggled the switch for the rear wiper/washer a couple of times. After I got home, no more whining noise. The switch for the rear washer apparently stuck internally in the on position, causing the rear washer motor to continuously run even when the engine was off. So far no repeats of the problem.