The radiator fan is coming on sometimes for no apparent reason, as often the engine has only just been started and the radiator is cold. However, on other ocasions there is no problem whatsoever. Last month I had a new cambelt fitted (at 21,825 miles) when the car became 5 years old, and also the air conditioning unit was re-gassed. Could there be any association with this work and the problem I am now experiencing, or is it perhaps due to a fault which lies somewhere else?