Engine Cooling fan coming on even when freezing !

R

rogercat

Member
I'm rather confused around my engine cooling fan on my 51 plate 1.4 TDI. It appears to be coming on on engine startup then might go of... then come on again etc. This is even occurring when temperatures are near freezing and car engine is cold to warm.
Presuming this is unusual behavior what should i replace - usually a electrical switch screwed into radiator ? I had a look at ELSA but could not find any info or diagrams.

Roger
 
You ideally need a diagnostic scan before you do anything or spend any money. This should identify the problem area (if there is one).

You may be worrying un-necessarily.

Cheers,

Mike
 
Can I do a diagnostic scan using freeware VAGcom, that's all I have ? I suppose its better the fan coming on too often than not at all !
 
You can certainly try it. The particular module or component may not be recognised by the free version, but fingers crossed.

Cheers,

Mike
 
Interestingly, from originally having overheating problems, which was due to the fan not operating at all, and having the fault repaired under warranty from the car saleroom (general car sales), I now have the cooling fan coming on from a cold start. The net result seems to be that it takes longer than usual to reach operating temp (90 deg) I assumed that this is not the correct behaviour and took it up with the car saleroom I bought it from. they then had it back for a day and said that the auto electrician had sorted the car and it was fine. A quick check shows that the fan still runs from the minute you start the engine, so I dont know whether I still have a fault or not? Can anyone shed any light on whether this is correct or am I being "fobbed off" rather than them spend money to sort it properly? I would not like to keep hassling the workshop manager if I do not have a problem.
 
Hi Scooter
The radiator fan Will run when the engine is cold if the climate control is switched on. There is a fan control unit above the radiator and this takes signals from two temp sender units in the cooling system (one in the bottom radiator hose and one on the engine I think) and activates the fan when required. There is also sender on the aircon system which triggers the radiator fan whenever the climate control is on, regardless of ambient temps.

Cheers Spike

Reply corrected after checking out erstens mail below
 
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But it allways runs slow, if the aircondition is on!! Does not depend on the engine temperature.
 
Hi erstens
You'r correct.... I checked it out this morning and even though it was cold enough for the auxiliary coolant heater to fire up, the radiator fan was running at slow speed. I switched of the climate control and the fan stopped.
As my wife always says to me, You'r not often right but you'r wrong again.
I have amended my previous mail to show the fan runs whenever the aircon is on.

Cheers Spike
 
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Yes. This must be because the climate-cooler where the gas gets comressed has to bee cooled.
I mean: inside the car were the liquid gas inside the climate system gets decompressed, it becomes cold (cools the inside of the car) and right this energy has to be trasported out of the car and this happenes in the cooler for the climasystem. It gets warm there.
Because all cooling system are only (you can call it:) heat-pumps.
But if you ask me: I wouldn't let the fan run all the time with climat on. only if it gets warm there.
 
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Thanks for your assistance, I have to admit the fan speed is fairly low when checked from cold so it seems that all is as it should be. Just paranoia on my part I guess but good to know there are always people "in the know" willing to help with advice. Cheers.
 
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