# OVERHEATING / COOLING FAN RELAY?



## Audi-Sport (Jan 2, 2009)

My TTR has an overheating problem!

When driving round with the heaters on the car sits at 90c perfectly, however when the 'econ' button is pushed in the temperature starts to creep past 90c. Now after an inspection it appears that the second stage fan kicks in, however the first fan setting doesn't - hence the overheating. I've also noticed that when the climate is turned on the fan doesn't run either?

Last night we tried replacing the 'Rad Fan Switch' which didn't fix the problem.. My mechanic mate has suggested the 'Cooling Fan Relay Pack' maybe at fault (rectangular pack situated at the front of the car) - however at £100 I don't want to change this if its going to be the actual fan that is knackered!

Can anyone shed any light on this? [smiley=bigcry.gif]


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## leeq61 (Apr 20, 2007)

I have exactly the same problem :? so any help on this one guys would be helpful.


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## Audi-Sport (Jan 2, 2009)

My mechanic mate has just told me he thinks its' the fans that should be replaced as the first point of call!!!


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## Typhhon (Oct 28, 2006)

The fan controller is a first point. 
With your air con on the first fan should run. 
Does your run on pump work?
There are fuses etc to check too.

Vag Com or a similar VAG diag tool (full version) should allow a diagnosis and test of the fan controller. :wink:


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## Audi-Sport (Jan 2, 2009)

There is no fans running with the aircon on, however if the 'run on pump' you refer to is the one that runs after you turn the car off - yes that does work. However isn't that in the turbo rather that the radiators?


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## Typhhon (Oct 28, 2006)

If there is power to the fan and it aint running you have the fault......
If you dont have power then its 'somewhere' in the fan controller circuit...
But then what do I know?
You need a multimeter I suggest....
VAG COM would help as advised....

Careful there lies dragons that eat money in swapping bits at random...


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## Typhhon (Oct 28, 2006)

Anyone know if the two fans are on the same circuit as you could hot wire No 2 to No1 (simple diagnosis of a dud fan?)


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## Audi-Sport (Jan 2, 2009)

Just done some 12v test and the fans are getting power so they are f*cked.. great! The big one is 125+ vat and the small one is 78+vat - happy days! [smiley=bigcry.gif]

Anyone know anywhere to get audi parts cheap?


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## Typhhon (Oct 28, 2006)

Could try http://www.ttspares.com/ understand its better to fill in the request form...


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## Typhhon (Oct 28, 2006)

And theres a few breaking on ebay...


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## Audi-Sport (Jan 2, 2009)

Well a month on I thought I would update this thread for anyone using the search facility with a similar problem - and maybe they can learn from my mistake!

First of all, it was my fans that were at fault. Each fan has two speeds, put simply slow and fast. The fast speed was working on both fans cutting in and stopping my car from ever overheating. However, the slow speed on both fans wasn't working causing the running temperature to raise until the fast speed would cut in. However I made the mistake of using a TT-breaker who supplied me with two fans that didn't work correctly. So I paid £35 to have the fans fitted, and taken back out + postage of £35 to send them back so I p*ssed £70 up the wall trying to cut corners. My advise would be - when replacing electrical items make sure they have been tested correctly, or (as I will do from now on) always buy new!

I can however report that my car now runs perfectly, never going over 90c. A BIG thanks to WAK for diagnosing the problem over the phone without even seeing the car... My mechanic was going to start changing thermostats and other parts £££££@!


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## tylerroach (Aug 7, 2010)

Thanks for all the great posts. I am having the same problem and just found a new large fan on eBay for $70. My mechanic gave me a quote to replace the fan for $800 to do this job. They wanted to take the whole bumper off and the front of the car to replace the fan. How did you guys get to the fan to replace it?


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## ttpanos (Nov 8, 2009)

I also had the same problem, and ultimately was the water pump


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## rallycross (May 26, 2009)

sorry to drag up an older thread but have similar issue and questions about when high speed fans kick in.

Our TT (225) will only run the lower speed fan (both fans work).

When its hot and have been driving quick but then get stuck in slow moving traffic the temp guage goes up past 90, mid way between 90 and the next white dash on the guage (so its 3/4 quarters the way towards red but never red).

I'd expect the high speed fan to cut in before it goes so high up the guage but just getting low speed on both.

Have checked under the bonnet whilst stuck in traffic with the guage up this far and only low speed fan is running.

How can I check fan speeds without using vag.com?


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## toy4two (Jan 29, 2012)

same thing happened to me, turned out the plastic impeller on the water pump went. they are only designed to go 60k miles on the TT


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## rallycross (May 26, 2009)

toy4two said:


> same thing happened to me, turned out the plastic impeller on the water pump went. they are only designed to go 60k miles on the TT


thanks its unlikely to be that as it was done at same time as timing belt.

anyone know about the fan controllers?


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## Typhhon (Oct 28, 2006)

Fan controller located at the front under the nearside cross member.










Controls both fans and fan speed 1 or 2 and the A/C clutch
Failure normally means loss of A/C, run on pump and fans.
Cow to get to.
Have the test voltages/current list if you need.


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## shane_tt (Jul 15, 2012)

this happened to my mates the fans wa not kicking in in traffic changed the fuse worked fine


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## HIRAM (Feb 15, 2010)

This is quite a lengthy thread but worthy of your time IMO

http://uk-mkivs.net/forums/t/59897.aspx

Rob


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## Typhhon (Oct 28, 2006)

shane_tt said:


> this happened to my mates the fans wa not kicking in in traffic changed the fuse worked fine


A blown fuse is normally an indicator of something else being wrong.

Mine blew traced to incorrect wiring routing that had frayed and took out the fan controller.

Always worth checking for 'something' else being suspect.

Mind you with all this dammed rain I'm surprised they all haven't blown


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