I have a 2006 Honda Civic 2.2 CDTI. Recently the radiator fans have been coming on, continuously, as soon as I put the key in the ignition from cold.
I have changed the coolant temperature sensor as they're easy and cheap enough to replace but still the fans are coming on and also stay on for about 60 seconds after the car is switched off.
I'm trying to avoid taking it the garage and wondered if anyone knew what could be causing the fans to stay on continuously and if there was a way I could fix it myself.

 

Might have caused a problem with the cars coolant temperature sensor when you changed the sensor. Or there is a ground disconnected? I am not sure, you are in Europe and we don't have the luxury of the diesel Civics in North America.