We had our first measurable snow in western NY state this weekend. While going up a hill, I switched into 4 wheel drive, later when back on dry pavement I went to switch it off and nothing happened. It stayed in 4 wheel drive. The indicator light is flashing along with the 4-lo indicator. I tried all of the suggestions in the manual to get it out of 4 wheel drive with no success. I have an appointment at the local Toyota dealer this afternoon. Any suggestions on what is going on?