Renault Megane Window intermittent?

Check the wiring to the front door, pay particular attention to the wiring connector located in the front 'a' post. They have a habit of filling with water and corroding. The other problem is that water gets in to the door and gets inside the electric window motor control box and corrodes the circuit board. The fact that the lights do not dim when the switch is operated indicates that it is more likely to be a faulty control box. does the window regulator have any warranty ?