Hi guys.. I have an 02 Stilo 1.6 dynamic. Great car in the main but I have a problem that I would much appreciate any advice or a fix on.

Last night after the car had been parked for about three hours i went to it only to greeted by a noise that sounded like the radiator fan was on.. The battery was completely dead by then. I disconnected the battery leads and left it overnight. After getting a homestart recovery, I was advised to purchase a new battery which I did straight away. The garage fitted the battery and advised that my coolant was low so I had a couple of litres added.
With the new battery fitted, off I drove.. problom solved.. or so I thought. This eve I heard the noise of the fan operating from inside my house. I rushed out and started the car up, concerned for the new battery. Each time I then turned off the ignition, the fan started running again. I have located the radiator fan fuse and removed it for now. I did describe the intial events to the garage fitting the battery and obviously they just were confused that i was suggesting the radiator fan switched itself on and couldn't really offer advice.!!
All that I can recall that may be siginificant, is that earlier in the evening, I had inadvertantly driven through a large puddle on the kerside.
So.. how do i fix this... ?? Has anyone had the same issue with a stilo?

Firstly it sounds like you needlessly brought a new battery unfortunatly (out of interest where did you get it and how much as I might need a new one).

Secondly the fan is controled by an ECU I think (not sure which one) so it might be a fault with that.

Best waiting until someone who knows what the problem will be comes along

Jon.

The fan is controlled by a sensor (what isnt these days). I would honestly say that your fan temp sensor is faulty. It is not uncommon for a fan to run on after the engine has been switched off and the vehicle locked and left. This is only noticable on a hot days or when the car has been driven hard.

Definately sounds like a fan control switch/sensor. I would start the hunt there. Bear in mind that the sensor only triggers the fan, not powers it, so disconnecting the sensor (whilst probably trigering a fault) will stop the fan if it causing the problem. New sensor, coolant swap and you should be ok. Its worthwhile looking for leaks in your coolant system as low coolant levels could cause the sensor to bake and fail. Vauxhalls ecotec engines were notorious for cooking the sensor, so that it never ran the fan at all resulting in overheating even when coolant levels were normal. Perhaps FIAT have designed theirs the other way round. Not good for batteries, but it would stop the engine overheating.

I would think you have a water affected engine bay fuse panel B1. That's where both relays T6 and T7 for operating the rad fan at the two different speeds are located. For either of those to be energised then their ground connection is finding a way to earth. Look for contacts corrosion or water there


Relay T7 is the only one that's directly connected to the battery and so could run with ignition off (T6 needs ignition on) so T7 is the one I'd investigate

Decks, wouldnt this trigger a fault on the dash?

A short in the engine bay fuse box? No.
There's live feeds and earths there without the ignition even being on so it wouldn't have a clue. Absolutely anything bizarrre can happen when there are shorts around but a live relay will only need to find a path to earth somewhere, anywhere, even through another component, for it to energise and it will stay on until the battery goes flat

As Ketty has found, removing the fuse is the only way to stop it while that short circuit to earth is there

I've had a similar problem on a Brava. The problem was inside the relais.
Pulling the relais when the ignition was switched off was a temporary sollution (I was on holiday in Croatia). Back home I bought a new relais and no more problems (with the fan that is.....Hey it was still a FIAT).

gr J

Had the same problem during a very wet spell as said it was the relay shorting across in the engine bay fuse board took apart and cleaned up now all ok you will notice the fan relay has prongs to stop it being pushed to far down into the slots of the fuse board make sure the relay is not sat flush on the board but only as far as the prongs allow else when pushed flush the pins of the relay also cause a short on the fuse board if you see inside the fuse board it is easier to explain but worth a check.

Deckchair5 said:

That's where both relays T6 and T7 for operating the rad fan at the two different speeds are located.

Click to expand...

DC, can you confirm which relay is for which speed setting out of interest? And Do all Stilo's have a twin speed setting or only those with A/C or Climate?

Jon.

Yes a stuck relay will keep the rad fan on but it won't suddenly come on, on its own after you've left the car as Ketty experienced. It will be on all the time


DC, can you confirm which relay is for which speed setting out of interest?
T6 goes through a load resistor O1 so is the slower speed, T7 is the full speed


Do all Stilo's have a twin speed setting or only those with A/C or Climate?
The 1.2 1.4 and 1.6 engines are similar and have the two relay - two speed fan set relevant to the original poster


The others, the 1.8, 1.9 and 2.4 use an entirely different method, have no relays and their own rad fan ecu M150 to control fan speed

Whether they have a/c or not doesn't affect the engine coolant scheme but the a/c does affect rad fan operation

Deckchair5 said:

Whether they have a/c or not doesn't affect the engine coolant scheme but the a/c does affect rad fan operation

Click to expand...

And unlike alot of cars, with Stilo A/C is on cooling fan will cut in and out as required and not run constantly with A/C activted?

This is something I've never had a clear answer on and have always wondered if my Stilo's A/C works properly

For all engine sizes
the rad fan slow speed switches on when the engine temp reaches a certain level OR when the a/c linear pressure sensor reaches a certain level. If either reach higher thresholds then the rad fan is turned on at fast speed

For the 1.8 and larger engines the two speeds are done within the rad fan control unit M150

So the rad fan should only come on when there's a need to and not run constantly

Same problem to me tonight. But I hear the noise outside, jump from out to look what's happening. cooling fan runs, but car all day was standing. Disconnect battery, hope it's not to late for my battery.
Any advice. I think problem because it's allot moisture outside. Wher to start looking? Help me, thank you.

look what i found in fuse box..