In my renault megane fijdi whist driving the drivers window winds down randomly. Sometimes i'm unable to wind it back up. Think its a electrical fault rather than a faulty motor
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)
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