Recently, I was driving my 1999 Grand Voyager SE and made a stop, leaving a window open. When I returned to the van, my clock and radio, my window controls and my A/C control were non-functioning. I drove a while and then stopped again. When I returned to the van, everything began to work again. This has not happened again and I wonder if I should be concerned enough to take the van to my mechanic. Any input will be appreciated.