Radiator Fan Blues

[tsk1979]

I own a 41000 done DLS, and the car is giving a funny problem. When the car is switched off also the radiator fan keeps on running. This problem has happened just 3 times in 2 months. The fan keeps running till the battery is fully drained. According to Tata workshop guys the fan should stop immediately after ignition is switched off. So they suspect the ACC Relay(12v 50A). But the problem is they could not replicate the problem at the workshop despite multiple tries of swiching on and off. The repair guy told me to remove the fuse next time this happenes. Also they say they will change the relay and see if this happenes again. If yes it means wiring is faulty.

Anybody else faced such a problem? My suspect is the relay too as Tata electricals doing 40000+ is a miracle, but could there be any other cause apart from the wiring and Relay.

[Harrie]

The problem is bcas the thermostat switch that cuts off the radiator fan has melted and is not cutting off. I had a similar problem in my car.

[Gordon]

Isn't it true that the radiator fan keeps running for sometime after the car is switched off to cool the engine down??! If not, whats that noise that comes from the car after it is switched off.

[Harrie]

yes gordon that is correct. I think the radiator fan is connected to the battery directly and controlled only by the thermostat switch in some cars (the GTX and uno i know for sure) so even the key is switched off the fan runs till the temperature falls below a particular point when the thermostat switches off. but what happened in my case was, the thermostat switch melted and was not cutting off once the temperature falls also.

I think this is the same problem in his indica too.

[Deeps]

Gordon, i don't think thats the case with every car. We have discussed this somewhere before.

[Gordon]

Originally Posted by tsk1979

According to Tata workshop guys the fan should stop immediately after ignition is switched off.

wondering why the TATA guys said that?! Maybe like Deeps said, its different for some cars.

Originally Posted by Deeps

Gordon, i don't think thats the case with every car. We have discussed this somewhere before.

Deeps, could you give me the link?

[drifter]

Gordon, i don't think thats the case with every car. We have discussed this somewhere before.

Even i remember this discussion somewhere....i think i remember older fiat sienas doing this - keeping the cooling fan on for sometime even after the ignition was switched off...
And somehow im being reminded of a fire in the engine compartment...because the fan failed to switch off ... cant remember if it was a fiat or not. But i think it was discussed before on this forum.

Drifter

[tsk1979]

In the indica, when engine is switched off, the fan immediately cuts off irrespective of the engine temp. For example of car is hot with fan running and i switch off, i can actualy hear the fan shutting down. When i again bring the key to IGN position, with the car still off, the fan starts again as engine temp has not lessened to that position. Under no circumstances i have seen the fan running after engine off. Infact with engine off if i short the relay terminals, fan starts. This circuit is not even in the thermostat route. I also saw the wiring diagram. With ignition off the fan is always off and this is the relay which controls this. And unless some wire is shorted or relay is shorted fant wont run with ign off.

[tsk1979]

Nope, in tata when ign is off fan is always off irrespective of eng temp. Try this. Heat up the engine till fan starts running. Take out the fan fuse and let the temp needle climb to near red(Dont let it get red!!). Switch off the car and put in the fuse. Though engine is very hot fan wont run. I guess in other cars it may be different.

[nitinbhag]

Originally Posted by drifter

Even i remember this discussion somewhere....i think i remember older fiat sienas doing this - keeping the cooling fan on for sometime even after the ignition was switched off...

Thats correct.. the fan on my Siena 1.6 runs for a few seconds after the ignition is switched off.. the hotter the engine and ambient air temp, the longer the fan runs.. I am assuming the coolant pump also runs along with the fan as only then the engine innards will cool down..

How about the new Petras? Does this feature come on them?

[jassi]

I am guessing its normal for the radiator fan to run for sometime after I put off the engine. I just recently noticed this in my santro, after long drives, however when it rains the fan doesn't go on
just checking as I didn't see a conclusion to this thread

[panky12345]

tanveer, in case your fan doent switch off even when your ignition is off you have a wiring short. change the wiring and you'll be OK.

in case it runs continously on IGN mode onwards, your thermostat + fuse box is at fault.

[suman]

Originally Posted by panky12345

tanveer, in case your fan doent switch off even when your ignition is off you have a wiring short. change the wiring and you'll be OK.

in case it runs continously on IGN mode onwards, your thermostat + fuse box is at fault.

Panky, you are replying to a post which is more than two & a half years old

[jassi]

yeah i am sure not only the fan but the whole car has been replaced i just found this thread and so i decided to ask as I have started noticing this sound in my car for a good 3-5 mins after i park (i leave the key in there, while unloading my bag, music system, etc) however if i come back from driving in the rain the fan doesn't even go on.

Just felt that 3-5 mins is a lot - so thought i'd inquire !!

[panky12345]

Originally Posted by suman

Panky, you are replying to a post which is more than two & a half years old

arre yaar, thats why I thought how come tanveer's car has only 41K on the ODO. didnt notice the date.