Fiat Ducato - aircon fan keeps running with ignition switch off.

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Fiat Ducato - aircon fan keeps running with ignition switch off.


New member
May 3, 2010
I have a 2020 Hymer Yellowstone van conversion on a Fiat Ducato 2.3, multijet 2, 130bhp base vehicle. It has climate control cab aircon which I mostly leave always switched on. I have only owned the camper for 6 months, so haven't needed to test the cooling abilities of the aircon, but it appears to function as expected so far as maintaining the cab at the chosen temperature and demisting the windscreen on cold days are concerned.

Under the bonnet, there are two electric cooling fans, one in the centre of the radiatior for engine cooling, and the other, on the nearside of the engine compartment which only operates when the aircon is switched on and which, I presume, is a dedicated aircon fan.

I have been surprised at the fact that the aircon fan cycles on and off very frequently when the vehicle is stationary with the engine running (that's the only time I am able to hear it). Each "on" cycle lasts less than a couple of minutes with each "off" cycle lasting roughly the same amount of time. Usually, when either the aircon is switched off from the cab, or the engine ignition is switched off, the fan stops running. On a couple of occasions however, with both the aforementioned switches in the off position, the aircon fan has continued to run.

My efforts to stop it by re-starting the engine and switching the cab aircon and/or climate control off ultimately appear to silence the aircon fan, but I don't know whether it would have stopped running spontaneously after a time and whether it should be running with the ignition switched off in the first place.

I should add that on the few occasions this has happened, the outside temperatures have been low and the length of the journey before it happened was relatively short and relaxed.

Should this be occurring, or is it likely to be the symptom of faulty aircon control?