This is a common problem with Renault (they have the worst complaints history of electrical faults, I had 2 of them and they both did the same thing) One possible cure is to remove the rear wiper motor or open the cover and dry it with a hairdryer, spray it with some WD 40 and then seal it as best you can with plastic bags or cling film. Apparently moisture in the wiper motor affects the window circuits ( It worked with mine)
Bob, April 2012
