Renault Scenic II fan fails quite often. In some cases you may notice that not all speeds selected from dashboard works, or works occasionally. But most often fan stops working at all. Of course first step to check is fuses. If fuses seem to be OK then the only way to look is at fan speed controller (sometimes called fan resistor). The easiest and most expensive way is to call service leave them to do repairs. But if you have some engineering blood, you can do it yourself by spending less than hour of your time and probably only couple bucks.