Fiat ducato engine cooling fans problem

[collom]

Hi, I have a 2001 Hymer on a fiat ducato 2.8 tdid model. The engine has 2 cooling fans behind the radiator, one large to the outside and one smaller to the centre. For some reason the smaller one has started running constantly, initially when the van had been sitting outside my house for a few weeks. There is a box with 3 relays behind the rad, 2 of them being the same. 1 seems to be for each fan, and the centre fan stops when I remove the appropriate relay. I’ve swapped both and the fan runs for each one so relays would seem to be OK. I have left the one out to save my battery from going flat.

Please can anybody help with any ideas as I can’t find any info on this. I am assuming both fans are for engine cooling but don’t know what would control them and when they would normally come on.

Thanks, Trevor :-(

[Guest Tracker]

Hi Trevor and welcome to the forum.

 

I've never had your issue but in hot weather the fan(s) on Ducatos/Boxers do run on after the engine has stopped to reduce engine heat tand then they(it) stop.

 

This suggests to me that they are therostatically controlled and perhaps a temperature sender or thermostat somewhere on the radiator, cooling system, or on the engine could be your culprit?

 

I might well be wrong, and no doubt an expert will be along later to help but meanwhile it might be worth looking for something in the cooling system rather than the electic system?

[thebishbus]

HI Trevor. The fan temperatur control switches are, looking from the front, on the bottom right hand side of the radiator, I would suspect those first.

Brian B.

[Derek Uzzell]

As Briab B suggests, the switch (switches?) that control fan operation looks like the primesuspect.

 

http://www.motorhomefacts.com/ftoptitle-16367-ducato-cooling-fans.html