this is most likely a faulty fan resistor unit.they tend to pack upafter afew years.I have the same car and mine did the same thing.As the fan works,then that means its ok,so it's the resistor that has burnt out.They are available from renault dealers and aren't too expensive.To remove the old one you will need to take out the glovebox.Use the haynes manual for directions.The heater motor is behind it.Identify the make of motor and resistor,it will be either a Behr or Valeo,as your parts dept will want to know.Best take it with you.Or try a good scrapyard.resistors are easy to fit,being screwed to the motor with 1 screw.the resistor then is turned clockwise to remove from top of fan housing.Make sure wiring plug is pulled out first.Hope this info helps.
c.p.sheppard
June 2008
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