# Radiator fans constant running



## milanonick (Sep 15, 2013)

So I changed the thermostat today and all seems well in that department in terms of the engine reaching the correct temperature.

However, I now have another issue in that the radiator fans keep running even after the ignition is switched off. The only way to stop them is to disconnect the battery. I can then reconnect the battery and they remain off but as soon as the ignition is turned back on they fire into life and remain on until another disconnection of the battery.

I had thought about a dodgy relay stuck on but this doesn't explain why they don't instantly come back on when the battery is reconnected.

Any thoughts of what I should be checking?


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## Hoggy (May 8, 2002)

Hi milanonick, Fans will run with Ign off if temp high enough, so I would suspect Thermal switch 2/3rds down on passenger side of radiator. Perhaps it then requires a switched Ign live to close relay again once battery is reconnected, or just a much lower temp before thermal switch contacts open.
Otherwise Fan Control module beneath battery/tray. 
Hoggy.


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## milanonick (Sep 15, 2013)

Cheers Hoggy appreciate your response.

I changed the fan switch and was gutted to find that the problem persisted.

Good news though. I had a poke around in the fusebox and found that fuse 16 was missing so fitted a replacement and could then hear the electric pump run for a short period of time. Better than that though the radiator fan issue was sorted.

On checking, changing the thermostat sorted the cool air in the car and maybe its the placebo effect but I'm sure the car feels a little more responsive now it's running at the proper temperature.

Only downside being the stereo in safe mode and not having the code. Think thats a job for my fiancee to call in at Audi and see if she can smile sweetly


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## Hoggy (May 8, 2002)

Hi, Excellent result. 8) I recently mentioned fuse 16 & 25to another TTF member with fan probs. 
Hoggy.


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## barb (Jul 1, 2013)

If you get your stereo out and get the serial number you can get the code off the net. Or bloke on eBay does them for 3.99 I think it was. There was a thread on here the other day

Sent from AutoGuide.com Free App


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## milanonick (Sep 15, 2013)

Thanks Barb, I'll have a hunt around and see if I can find the thread. I could do with getting it done sooner rather than later as we can't get into Audi until next weekend.


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## milanonick (Sep 15, 2013)

Just to update should people be looking for a cheaper way to get their radio code other than Audi at £25.

After contacting Audi they were having none of "the manual says you'll give me the code for free" so I paid £5.99 for a code from an eBay seller http://www.ebay.co.uk/itm/161107352675? ... 1439.l2649

Great service and received the code in less than half an hour.

Hopefully that may help other members in the same predicament.

On a plus point Audi checked their records and couldn't see that the coilpack recall had been done so we are booked in for that.


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## Jas (Oct 15, 2013)

Hi Milanonick, first of all thanks. We bought tt six months ago and one day in traffic it started to over heat. Went on forums for help , there was no fuse in above battery for fans, fitted fuse and both fans came on then noticed fans came on as soon as you turn key to ignition and stayed on ten mins after turning engine off. then battery went flat ,got new battery that went flat also. We have changed fan relay , thermostat, coolant sensor and temperature switch without any joy no one had any other ideas. Tonight Thursday 21:50 I read your post and went out to car and put a fuse in 16 and joy fans did not come on . Thank again also we had car booked in at auto electricians tomorrow so we don't have to spend any more money on the problem.


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## Hoggy (May 8, 2002)

Hi Jas, Welcome to the TTF.
As you have found out the TTF, is the best place to be to fix TT probs....Why did it take you so long, :lol:  :wink: 
Hoggy.


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