Technical Cooling fan not cutting in

[alanandalan]

Hi everone just after a bit of advice, got a 1.2 Stilo and it seems the cooling fan is not cutting in, whilst in slow moving traffic yesterday the temperature guage creeped up to the red mark.Checked the big maxi fuses next to the battery they are ok, i have not tried to turn to fan to see if its stiff.So dont know if its the fan, a relay, or sensor not working? Any sugestions welcolmed. I read somewhere in the tech section the easy way to test the fan, is to switch the ignition on and unplug the temp sender, if the fan is ok it should start after about 10 secs, is this true, also where is the sensor? I did try messing about with the fiatecu programme, as you can test both fan speeds but nothing happened, but i was also having conection probs with the laptop at the time. Thanks Alan

 

[MarkThompson4]

The temp sensor is just behind the thermostat, it's a green colour hard to miss just remove the wiring plug from it, personally I've not heard of that making the fan kick in but worth a shot.

 

[Most Easterly Pandas]

The temp sensor is just behind the thermostat, it's a green colour hard to miss just remove the wiring plug from it, personally I've not heard of that making the fan kick in but worth a shot.

I believe it does as a safety measure, programmed into the ECU

 

[alanandalan]

Well i had another look at the stilo today, the fan turns easily by hand so is not seized, i unplugged the temp sensor to see what would happen, nothing, apart from a slight whering sound, fom some box on the engine but not the fan. plugged in fiatecuscan, hand had message come up coolant temp sensor critical failure, messed about and managed to clear that fault. I also tried to activate the fan, both speed 1 and speed 2 via fiatecuscan, nothing came up with message fan inactive ?? messed about a bit more and managed to get message saying fan speeds 1 &2 active, run the fan speed test and nothing happenes. so will try unplugging the fan motor wires and conect the fan to the battery by 2 wires and see if the fan works. i hate bloody electrics.

 

[alanandalan]

well i have conected the fan directally to the batteryy and the fan works, so that has been ruled out, just need to find out what else could be causing the fan not to cut in?

 

[varesecrazy]

I would change the coolant temp. sensor,
cheap and relatively easy,
Charlie

 

[Most Easterly Pandas]

I would change the coolant temp. sensor,
cheap and relatively easy,
Charlie

If the temp on the dash is reading correctly then this is pointless as they use the same sensor on the Canbus controlled systems.

Next is to check the wiring to the fan in origional loom.

 

[alanandalan]

Hi again everyone, yes the temp guage does work, so check the wireing you think, whatever a canbus is ? thanks

 

[alanandalan]

Ps its not likely to be a relay out is it ?? Ta

 

[Most Easterly Pandas]

Ps its not likely to be a relay out is it ?? Ta

Potentially, this is where I'd start.

Canbus is the computer system which controls the car and it's bits, everything from lights to electroc windows to wipers

 

[12[X]]

sure this is not needed but i'm bored

https://www.fiatforum.com/stilo-gui...engines-radiator-fan-slow-speed-resistor.html

 

[alanandalan]

Hi to those that may be interested, finally got the rad fan sorted, took itt someone who knew what they were doing:nerner:. The problem fan speed 1 did not work was the resistor , and the reason fan speed 2 does not work, is aircon needs re gassing, cost £154.00 in total, resistor £42 plus diagnostics 50 quid half hour labour, and the vat. I could have easily spent that much putting bits on in trial and error. Glad its sorted in this heat. Cheers all.